VMware vRealize Operations Manager 6.x tc Server Security Technical Implementation Guide

Resource exhaustion can occur when an unlimited number of concurrent requests are allowed on a website, facilitating a denial-of-service attack. Mitigating this kind of attack will include limiting the number of concurrent HTTP/HTTPS requests. Mitigating this kind of attack will include limiting the number of concurrent HTTP/HTTPS requests. Each incoming request requires a thread for the duration of that request. If more simultaneous requests are received than can be handled by the currently available request processing threads, additional threads will be created up to the value of the "maxThreads" attribute.

Resource exhaustion can occur when an unlimited number of concurrent requests are allowed on a website, facilitating a denial-of-service attack. Mitigating this kind of attack will include limiting the number of concurrent HTTP/HTTPS requests.

Mitigating this kind of attack will include limiting the number of concurrent HTTP/HTTPS requests. Each incoming request requires a thread for the duration of that request. If more simultaneous requests are received than can be handled by the currently available request processing threads, additional threads will be created up to the value of the "maxThreads" attribute.

Denial of Service is one threat against web servers. Many DoS attacks attempt to consume web server resources in such a way that no more resources are available to satisfy legitimate requests. Mitigation against these threats is to take steps to limit the number of resources that can be consumed in certain ways.

tc Server provides the "connectionTimeout" attribute. This sets the number of milliseconds tc Server will wait, after accepting a connection, for the request URI line to be presented. This timeout will also be used when reading the request body (if any).

KeepAlive provides long-lived HTTP sessions that allow multiple requests to be sent over the same connection. Enabling KeepAlive mitigates the effects of several types of denial-of-service attacks.

An advantage of KeepAlive is the reduced latency in subsequent requests (no handshaking). However, a disadvantage is that server resources are not available to handle other requests while a connection is maintained between the server and the client.

tc Server can be configured to limit the number of subsequent requests that one client can submit to the server over an established connection. This limit helps provide a balance between the advantages of KeepAlive, while not allowing any one connection being held too long by any one client. "maxKeepAliveRequests" is the tc Server attribute which sets this limit.

KeepAlive provides long-lived HTTP sessions that allow multiple requests to be sent over the same connection. Enabling KeepAlive mitigates the effects of several types of denial-of-service attacks.

An advantage of KeepAlive is the reduced latency in subsequent requests (no handshaking). However, a disadvantage is that server resources are not available to handle other requests while a connection is maintained between the server and the client.

tc Server can be configured to limit the number of subsequent requests that one client can submit to the server over an established connection. This limit helps provide a balance between the advantages of KeepAlive, while not allowing any one connection being held too long by any one client. "maxKeepAliveRequests" is the tc Server attribute that sets this limit.

Cookies are a common way to save session state over the HTTP(S) protocol. If an attacker can compromise session data stored in a cookie, they are better able to launch an attack against the server and its applications.

Session cookies stored on the server are more secure than cookies stored on the client. Therefore, tc Server must be configured correctly in order to generate and manage session cookies on the server. Managing cookies on the server provides a layer of defense to vRealize Automation.

By default, tc Server is designed to manage cookies on the server. However, incorrect configuration can turn off the default feature.

Encryption of data-in-flight is an essential element of protecting information confidentiality. If a web server uses weak or outdated encryption algorithms, then the server's communications can potentially be compromised.

The US Federal Information Processing Standards (FIPS) publication 140-2, Security Requirements for Cryptographic Modules (FIPS 140-2) identifies eleven areas for a cryptographic module used inside a security system that protects information. FIPS 140-2- approved ciphers provide the maximum level of encryption possible for a private web server.

Configuration of ciphers used by tc Server are set in the "catalina.properties" file. Only those ciphers specified in the configuration file, and which are available in the installed OpenSSL library, will be used by tc Server while encrypting data for transmission.

Encryption of data-in-flight is an essential element of protecting information confidentiality. If a web server uses weak or outdated encryption algorithms, then the server's communications can potentially be compromised.

The US Federal Information Processing Standards (FIPS) publication 140-2, Security Requirements for Cryptographic Modules (FIPS 140-2) identifies eleven areas for a cryptographic module used inside a security system that protects information. FIPS 140-2-approved ciphers provide the maximum level of encryption possible for a private web server.

Configuration of ciphers used by tc Server are set in the "catalina.properties" file. Only those ciphers specified in the configuration file, and which are available in the installed OpenSSL library, will be used by tc Server while encrypting data for transmission.

Data exchanged between the user and the web server can range from static display data to credentials used to log into the hosted application. Even when data appears to be static, the non-displayed logic in a web page may expose business logic or trusted system relationships. The integrity of all the data being exchanged between the user and web server must always be trusted. To protect the integrity and trust, encryption methods should be used to protect the complete communication session.

HTTP connections in tc Server are managed through the Connector object. Setting the Connector's "SSLEnabled" flag, SSL handshake/encryption/decryption is enabled.

Remote access can be exploited by an attacker to compromise the server. By recording all remote access activities, it will be possible to determine the attacker's location, intent, and degree of success.

As a Tomcat derivative, tc Server can be configured with an "AccessLogValve". A Valve element represents a component that can be inserted into the request processing pipeline. The Access Log Valve creates log files in the same format as those created by standard web servers.

Remote access can be exploited by an attacker to compromise the server. By recording all remote access activities, it will be possible to determine the attacker's location, intent, and degree of success.

As a Tomcat derivative, tc Server can be configured with an "AccessLogValve". A Valve element represents a component that can be inserted into the request processing pipeline. The Access Log Valve creates log files in the same format as those created by standard web servers.

Log records can be generated from various components within the web server (e.g., httpd, plug-ins to external backends, etc.). From a web server perspective, certain specific web server functionalities may be logged as well. The web server must allow the definition of what events are to be logged. As conditions change, the number and types of events to be logged may change, and the web server must be able to facilitate these changes.

As a Tomcat derivative, tc Server can be configured with an "AccessLogValve". A Valve element represents a component that can be inserted into the request processing pipeline. The pattern attribute of the "AccessLogValve" controls which data gets logged.

Log records can be generated from various components within the web server (e.g., httpd, plug-ins to external backends, etc.). From a web server perspective, certain specific web server functionalities may be logged as well. The web server must allow the definition of what events are to be logged. As conditions change, the number and types of events to be logged may change, and the web server must be able to facilitate these changes.

As a Tomcat derivative, tc Server can be configured with an "AccessLogValve". A Valve element represents a component that can be inserted into the request processing pipeline. The pattern attribute of the "AccessLogValve" controls which data gets logged.

After a security incident has occurred, investigators will often review log files to determine what happened. Understanding what type of event occurred is critical for investigation of a suspicious event.

Like all servers, tc Server will typically process "GET" and "POST" requests clients. These will help investigators understand what happened.

After a security incident has occurred, investigators will often review log files to determine what happened. Understanding what type of event occurred is critical for investigation of a suspicious event.

Like all servers, tc Server will typically process "GET" and "POST" requests clients. These will help investigators understand what happened.

After a security incident has occurred, investigators will often review log files to determine when events occurred. Understanding the precise sequence of events is critical for investigation of a suspicious event.

As a Tomcat derivative, tc Server can be configured with an "AccessLogValve". A Valve element represents a component that can be inserted into the request processing pipeline. The pattern attribute of the "AccessLogValve" controls which data gets logged. The "%t" parameter specifies that the system time should be recorded.

After a security incident has occurred, investigators will often review log files to determine what happened. tc Server HORIZON must create a log entry when a user accesses the system and the system authenticates users.

The logs must contain information about user sessions to include what type of event occurred, when (date and time) events occurred, where within the server the events occurred, the client source of the events, the outcome (success or failure) of the event, the identity of the user/subject/process associated with the event.

Like all web servers, tc Server will log the requested URL and the parameters, if any, sent in the request. This information will enable investigators to determine where in the server an action was requested.

After a security incident has occurred, investigators will often review log files to determine what happened. tc Server HORIZON must create a log entry when a user accesses the system and the system authenticates users.

The logs must contain information about user sessions to include what type of event occurred, when (date and time) events occurred, where within the server the events occurred, the client source of the events, the outcome (success or failure) of the event, the identity of the user/subject/process associated with the event.

Like all web servers, tc Server will log the requested URL and the parameters, if any, sent in the request. This information will enable investigators to determine where in the server an action was requested.

After a security incident has occurred, investigators will often review log files to determine what happened. tc Server HORIZON must create a log entry when a user accesses the system and the system authenticates users.

The logs must contain information about user sessions to include what type of event occurred, when (date and time) events occurred, where within the server the events occurred, the client source of the events, the outcome (success or failure) of the event, the identity of the user/subject/process associated with the event.

As a Tomcat derivative, tc Server can be configured with an "AccessLogValve". A Valve element represents a component that can be inserted into the request processing pipeline. The pattern attribute of the "AccessLogValve" controls which data gets logged. The "%h" parameter will record the remote hostname or IP address that sent the request; i.e. the source of the event.

tc Server HORIZON logging capability is critical for accurate forensic analysis. Without sufficient and accurate information, a correct replay of the events cannot be determined.

Ascertaining the correct source, e.g. source IP, of the events is important during forensic analysis. Correctly determining the source of events will add information to the overall reconstruction of the logable event. By determining the source of the event correctly, analysis of the enterprise can be undertaken to determine if events tied to the source occurred in other areas within the enterprise.

tc Server HORIZON must be configured with the "RemoteIpValve" element in order to record the Client source vice the load balancer or proxy server as the source of every logable event. The "RemoteIpValve" enables the "x-forward-* HTTP" properties, which are used by the load balance to provide the client source.

tc Server HORIZON logging capability is critical for accurate forensic analysis. Without sufficient and accurate information, a correct replay of the events cannot be determined.

Ascertaining the correct source, e.g. source IP, of the events is important during forensic analysis. Correctly determining the source of events will add information to the overall reconstruction of the logable event. By determining the source of the event correctly, analysis of the enterprise can be undertaken to determine if events tied to the source occurred in other areas within the enterprise.

tc Server HORIZON must be configured with the "RemoteIpValve" element in order to record the Client source vice the load balancer or proxy server as the source of every logable event. The "RemoteIpValve" enables the "x-forward-* HTTP" properties, which are used by the load balance to provide the client source.

After a security incident has occurred, investigators will often review log files to determine what happened. tc Server HORIZON must create a log entry when a user accesses the system and the system authenticates users.

The logs must contain information about user sessions to include what type of event occurred, when (date and time) events occurred, where within the server the events occurred, the client source of the events, the outcome (success or failure) of the event, the identity of the user/subject/process associated with the event.

Like all web servers, tc Server generates HTTP status codes. The status code is a three-digit indicator of the outcome of the server's response to the request.

After a security incident has occurred, investigators will often review log files to determine what happened. tc Server HORIZON must create a log entry when a user accesses the system and the system authenticates users.

The logs must contain information about user sessions to include what type of event occurred, when (date and time) events occurred, where within the server the events occurred, the client source of the events, the outcome (success or failure) of the event, the identity of the user/subject/process associated with the event.

As a Tomcat derivative, tc Server can be configured with an "AccessLogValve". A Valve element represents a component that can be inserted into the request processing pipeline. The pattern attribute of the "AccessLogValve" controls which data gets logged. The "%u" parameter will record the remote user that was authenticated. Knowing the authenticated user could be crucial to know in an investigation.

After a security incident has occurred, investigators will often review log files to determine what happened. tc Server HORIZON must create a log entry when a user accesses the system and the system authenticates users.

The logs must contain information about user sessions to include what type of event occurred, when (date and time) events occurred, where within the server the events occurred, the client source of the events, the outcome (success or failure) of the event, the identity of the user/subject/process associated with the event.

As a Tomcat derivative, tc Server can be configured with an "AccessLogValve". A Valve element represents a component that can be inserted into the request processing pipeline. The pattern attribute of the "AccessLogValve" controls which data gets logged. The "%u" parameter will record the remote user that was authenticated. Knowing the authenticated user could be crucial to know in an investigation.

Log data is essential in the investigation of events. If log data were to become compromised, then competent forensic analysis and discovery of the true source of potentially malicious system activity would be difficult, if not impossible, to achieve. In addition, access to log records provides information an attacker could potentially use to their advantage since each event record might contain communication ports, protocols, services, trust relationships, user names, etc.

The web server must protect the log data from unauthorized read, write, copy, etc. This can be done by the web server if the web server is also doing the logging function. The web server may also use an external log system. In either case, the logs must be protected from access by non-privileged users.

Log data is essential in the investigation of events. If log data were to become compromised, then competent forensic analysis and discovery of the true source of potentially malicious system activity would be difficult, if not impossible, to achieve. In addition, access to log records provides information an attacker could potentially use to their advantage since each event record might contain communication ports, protocols, services, trust relationships, user names, etc.

The web server must protect the log data from unauthorized read, write, copy, etc. This can be done by the web server if the web server is also doing the logging function. The web server may also use an external log system. In either case, the logs must be protected from access by non-privileged users.

Log data is essential in the investigation of events. The accuracy of the information is always pertinent. Information that is not accurate does not help in the revealing of potential security risks and may hinder the early discovery of a system compromise. One of the first steps an attacker will undertake is the modification or deletion of log records to cover his tracks and prolong discovery.

The web server must protect the log data from unauthorized modification. This can be done by the web server if the web server is also doing the logging function. The web server may also use an external log system. In either case, the logs must be protected from modification by non-privileged users.

Log data is essential in the investigation of events. The accuracy of the information is always pertinent. Information that is not accurate does not help in the revealing of potential security risks and may hinder the early discovery of a system compromise. One of the first steps an attacker will undertake is the modification or deletion of audit records to cover his tracks and prolong discovery.

The web server must protect the log data from unauthorized deletion. This can be done by the web server if the web server is also doing the logging function. The web server may also use an external log system. In either case, the logs must be protected from deletion by non-privileged users.

Log data is essential in the investigation of events. The accuracy of the information is always pertinent. Information that is not accurate does not help in the revealing of potential security risks and may hinder the early discovery of a system compromise. One of the first steps an attacker will undertake is the modification or deletion of audit records to cover his tracks and prolong discovery.

The web server must protect the log data from unauthorized deletion. This can be done by the web server if the web server is also doing the logging function. The web server may also use an external log system. In either case, the logs must be protected from deletion by non-privileged users.

Being able to verify that a patch, upgrade, certificate, etc., being added to the web server is unchanged from the producer of the file is essential for file validation and non-repudiation of the information.

VMware delivers product updates and patches regularly. It is crucial that system administrators coordinate installation of product updates with the site ISSO to ensure that only valid files are uploaded onto the system.

User management and authentication can be an essential part of any application hosted by the web server. Along with authenticating users, the user management function must perform several other tasks like password complexity, locking users after a configurable number of failed logins, and management of temporary and emergency accounts; and all of this must be done enterprise-wide.

For historical reasons, tc Server contains a tomcat-users.xml file in the configuration directory. This file was originally used by standalone applications that did not authenticate against an LDAP or other enterprise mechanism. vROps does not use this file.

User management and authentication can be an essential part of any application hosted by the web server. Along with authenticating users, the user management function must perform several other tasks like password complexity, locking users after a configurable number of failed logins, and management of temporary and emergency accounts; and all of this must be done enterprise-wide.

For historical reasons, tc Server contains a "tomcat-users.xml" file in the configuration directory. This file was originally used by standalone applications that did not authenticate against an LDAP or other enterprise mechanism. vROps does not use this file.

Web server documentation, sample code, example applications, and tutorials may be an exploitable threat to a web server because this type of code has not been evaluated and approved. A production web server must only contain components that are operationally necessary (e.g., compiled code, scripts, web-content, etc.).

Any documentation, sample code, example applications, and tutorials must be removed from a production web server. Because tc Server is installed as part of the entire vROps application, and not installed separately, VMware has ensured that all documentation, sample code, example applications, and tutorials have been removed from tc Server as part of the build process.

Controlling what a user of a hosted application can access is part of the security posture of the web server. Any time a user can access more functionality than is needed for the operation of the hosted application poses a security issue. A user with too much access can view information that is not needed for the user's job role, or the user could use the function in an unintentional manner.

A MIME tells the web server what type of program various file types and extensions are and what external utilities or programs are needed to execute the file type.

tc Server configures MIME types in the web.xml file. By ensuring that "sh", "csh", and "shar" MIME types are not included in web.xml, the server is protected against malicious users tricking the server into executing shell command files.

Resource mapping is the process of tying a particular file type to a process in the web server that can serve that type of file to a requesting client and to identify which file types are not to be delivered to a client.

By not specifying which files can and which files cannot be served to a user, the web server could deliver to a user web server configuration files, log files, password files, etc.

As a derivative of the Apache Tomcat project, tc Server is a java-based web server. As a result, the main file extension used by tc Server is "*.jsp". This check ensures that the "*.jsp" file type has been properly mapped to servlets.

Resource mapping is the process of tying a particular file type to a process in the web server that can serve that type of file to a requesting client and to identify which file types are not to be delivered to a client.

By not specifying which files can and which files cannot be served to a user, the web server could deliver to a user web server configuration files, log files, password files, etc.

As a derivative of the Apache Tomcat project, tc Server is a java-based web server. As a result, the main file extension used by tc Server is "*.jsp". This check ensures that the "*.jsp" file type has been properly mapped to servlets.

The Java Runtime environment can cause a memory leak or lock files under certain conditions. Without memory leak protection, tc Server HORIZON can continue to consume system resources which will lead to OutOfMemoryErrors when re-loading web applications.

Memory leaks occur when JRE code uses the context class loader to load a singleton as this will cause a memory leak if a web application class loader happens to be the context class loader at the time. The JreMemoryLeakPreventionListener class is designed to initialize these singletons when Tomcat's common class loader is the context class loader.

Proper use of JRE memory leak protection will ensure that the hosted application does not consume system resources and cause an unstable environment.

The Java Runtime environment can cause a memory leak or lock files under certain conditions. Without memory leak protection, tc Server HORIZON can continue to consume system resources which will lead to OutOfMemoryErrors when re-loading web applications.

Memory leaks occur when JRE code uses the context class loader to load a singleton as this will cause a memory leak if a web application class loader happens to be the context class loader at the time. The JreMemoryLeakPreventionListener class is designed to initialize these singletons when Tomcat's common class loader is the context class loader.

Proper use of JRE memory leak protection will ensure that the hosted application does not consume system resources and cause an unstable environment.

A web server is designed to deliver content and execute scripts or applications on the request of a client or user. Containing user requests to files in the directory tree of the hosted web application and limiting the execution of scripts and applications guarantees that the user is not accessing information protected outside the application's realm.

By checking that no symbolic links exist in the document root, the web server is protected from users jumping outside the hosted application directory tree and gaining access to the other directories, including the system root.

The web server must be configured to listen on a specified IP address and port. Without specifying an IP address and port for the web server to utilize, the web server will listen on all IP addresses available to the hosting server. If the web server has multiple IP addresses, i.e., a management IP address, the web server will also accept connections on the management IP address.

Accessing the hosted application through an IP address normally used for non-application functions opens the possibility of user access to resources, utilities, files, ports, and protocols that are protected on the desired application IP address.

The web server must be configured to listen on a specified IP address and port. Without specifying an IP address and port for the web server to utilize, the web server will listen on all IP addresses available to the hosting server. If the web server has multiple IP addresses, i.e., a management IP address, the web server will also accept connections on the management IP address.

Accessing the hosted application through an IP address normally used for non-application functions opens the possibility of user access to resources, utilities, files, ports, and protocols that are protected on the desired application IP address.

Data used to authenticate, especially passwords, needs to be protected at all times, and encryption is the standard method for protecting authentication data during transmission. Data used to authenticate can be passed to and from the web server for many reasons.

Examples include data passed from a user to the web server through an HTTPS connection for authentication, the web server authenticating to a backend database for data retrieval and posting, and the web server authenticating to a clustered web server manager for an update.

HTTP connections in tc Server are managed through the Connector object. Setting the Connector's "SSLEnabled" flag, SSL handshake/encryption/decryption is enabled.

The DoD standard for authentication is DoD-approved PKI certificates. A certificate’s certification path is the path from the end entity certificate to a trusted root certification authority (CA). Certification path validation is necessary for a relying party to make an informed decision regarding acceptance of an end entity certificate. Certification path validation includes checks such as certificate issuer trust, time validity and revocation status for each certificate in the certification path. Revocation status information for CA and subject certificates in a certification path is commonly provided via certificate revocation lists (CRLs) or online certificate status protocol (OCSP) responses.

The web server's private key is used to prove the identity of the server to clients and securely exchange the shared secret key used to encrypt communications between the web server and clients.

By gaining access to the private key, an attacker can pretend to be an authorized server and decrypt the SSL traffic between a client and the web server.

As a Tomcat derivative tc Server is designed to store the server's private key in a keystore file. An important vROps keystore file is "tcserver.truststore", and this file must be protected to only allow system administrators and other authorized users to have access to it.

Encryption is only as good as the encryption modules utilized. Unapproved cryptographic module algorithms cannot be verified and cannot be relied upon to provide confidentiality or integrity, and DoD data may be compromised due to weak algorithms.

FIPS 140-2 is the current standard for validating cryptographic modules and NSA Type-X (where X=1, 2, 3, 4) products are NSA-certified, hardware-based encryption modules.

vROps relies upon the OpenSSL suite of encryption libraries. A special carefully defined software component called the OpenSSL FIPS Object Module has been created from the OpenSSL libraries to provide FIPS 140-2 validated encryption. This Module was designed for compatibility with OpenSSL so that products using the OpenSSL API can be converted to use validated cryptography with minimal effort.

As a rule, accounts on a web server are to be kept to a minimum. Only administrators, web managers, developers, auditors, and web authors require accounts on the machine hosting the web server. The resources to which these accounts have access must also be closely monitored and controlled. Only the system administrator needs access to all the system's capabilities, while the web administrator and associated staff require access and control of the web content and web server configuration files.

As with all secure web server installations, tc Server files and directories must be adequately protected with correct permissions.

As a rule, accounts on a web server are to be kept to a minimum. Only administrators, web managers, developers, auditors, and web authors require accounts on the machine hosting the web server. The resources to which these accounts have access must also be closely monitored and controlled. Only the system administrator needs access to all the system's capabilities, while the web administrator and associated staff require access and control of the web content and web server configuration files.

As with all secure web server installations, tc Server files and directories must be adequately protected with correct permissions.

In order to properly monitor the changes to the web server and the hosted applications, logging must be enabled. Along with logging being enabled, each record must properly contain the changes made and the names of those who made the changes.

Allowing anonymous users the capability to change the web server or the hosted application will not generate proper log information that can then be used for forensic reporting in the case of a security issue. Allowing anonymous users to make changes will also grant change capabilities to anybody without forcing a user to authenticate before the changes can be made.

Making certain that the web server has not been updated by an unauthorized user is always a concern. Adding patches, functions, and modules that are untested and not part of the baseline opens the possibility for security risks. The web server must offer, and not hinder, a method that allows for the quick and easy reinstallation of a verified and patched baseline to guarantee the production web server is up-to-date and has not been modified to add functionality or expose security risks.

Because tc Server is installed as part of the entire vROps application, and not installed separately, VMware has ensured that all updates, upgrades, and patches have been thoroughly tested before becoming part of the production build process.

Determining a safe state for failure and weighing that against a potential DoS for users depends on what type of application the web server is hosting. For an application presenting publicly available information that is not critical, a safe state for failure might be to shut down for any type of failure; but for an application that presents critical and timely information, a shutdown might not be the best state for all failures.

Performing a proper risk analysis of the hosted applications and configuring the web server according to what actions to take for each failure condition will provide a known fail safe state for the web server. The VMware engineering process includes regression testing of new and modified components before they become part of the production build process.

A web server is used to deliver content on the request of a client. The content delivered to a client must be controlled, allowing only hosted application files to be accessed and delivered. To allow a client access to system files of any type is a major security risk that is entirely avoidable. Obtaining such access is the goal of directory traversal and URL manipulation vulnerabilities. To facilitate such access by misconfiguring the web document (home) directory is a serious error. In addition, having the path on the same drive as the system folder compounds potential attacks such as drive space exhaustion.

As a Tomcat derivative, tc Server stores the web applications in a special "webapps" folder. The Java engine, however, is stored in a separate are of the OS directory structure. For greatest security it is important to verify that the "webapps" and the Java directories remain separated.

A web server is used to deliver content on the request of a client. The content delivered to a client must be controlled, allowing only hosted application files to be accessed and delivered. To allow a client access to system files of any type is a major security risk that is entirely avoidable. Obtaining such access is the goal of directory traversal and URL manipulation vulnerabilities. To facilitate such access by misconfiguring the web document (home) directory is a serious error. In addition, having the path on the same drive as the system folder compounds potential attacks such as drive space exhaustion.

As a Tomcat derivative, tc Server stores the web applications in a special "webapps" folder. The Java engine, however, is stored in a separate are of the OS directory structure. For greatest security it is important to verify that the "webapps" and the Java directories remain separated.

Cross-site scripting (XSS) is a type of computer security vulnerability typically found in web applications. XSS enables attackers to inject client-side scripts into web pages viewed by other users. A cross-site scripting vulnerability may be used by attackers to bypass access controls such as the same-origin policy.

As a web server, tc Server can be vulnerable to XSS if steps are not taken to mitigate the threat. VMware provides the XssFilter component to provide a layer of defense against XSS. Filters are Java objects that performs filtering tasks on either the request to a resource (a servlet or static content), or on the response from a resource, or both.

Invalid user input occurs when a user inserts data or characters into a hosted application's data entry field and the hosted application is unprepared to process that data. This results in unanticipated application behavior, potentially leading to an application compromise. Invalid user input is one of the primary methods employed when attempting to compromise an application.

An attacker can also enter Unicode into hosted applications in an effort to break out of the document home or root home directory or to bypass security checks.

To mitigate against many types of character-based vulnerabilities, tc Server should be configured to use a consistent character set. The "URIEncoding" attribute on the Connector nodes provides the means for tc Server to enforce a consistent character set encoding.

Invalid user input occurs when a user inserts data or characters into a hosted application's data entry field and the hosted application is unprepared to process that data. This results in unanticipated application behavior, potentially leading to an application compromise. Invalid user input is one of the primary methods employed when attempting to compromise an application.

An attacker can also enter Unicode into hosted applications in an effort to break out of the document home or root home directory or to bypass security checks.

To mitigate against many types of character-based vulnerabilities, tc Server should be configured to use a consistent character set. The "URIEncoding" attribute on the Connector nodes provides the means for tc Server to enforce a consistent character set encoding.

Invalid user input occurs when a user inserts data or characters into a hosted application's data entry field and the hosted application is unprepared to process that data. This results in unanticipated application behavior, potentially leading to an application compromise. Invalid user input is one of the primary methods employed when attempting to compromise an application.

An attacker can also enter Unicode into hosted applications in an effort to break out of the document home or root home directory or to bypass security checks.

As a web server, tc Server can be vulnerable to character encoding attacks if steps are not taken to mitigate the threat. VMware utilizes the standard Tomcat setCharacterEncodingFilter filter to provide a layer of defense against character encoding attacks. Filters are Java objects that performs filtering tasks on either the request to a resource (a servlet or static content), or on the response from a resource, or both.

The goal is to completely control the web user's experience in navigating any portion of the web document root directories. Ensuring all web content directories have at least the equivalent of an index.html file is a significant factor to accomplish this end.

Enumeration techniques, such as URL parameter manipulation, rely upon being able to obtain information about the web server's directory structure by locating directories without default pages. In the scenario, the web server will display to the user a listing of the files in the directory being accessed. By having a default hosted application web page, the anonymous web user will not obtain directory browsing information or an error message that reveals the server type and version.

As a web server, tc Server can be vulnerable to enumeration techniques if steps are not taken to mitigate the vulnerability. Ensuring that every document directory has an "index.jsp" (or equivalent) file is one common sense approach to mitigating the vulnerability.

The goal is to completely control the web user's experience in navigating any portion of the web document root directories. Ensuring all web content directories have at least the equivalent of an index.html file is a significant factor to accomplish this end.

Enumeration techniques, such as URL parameter manipulation, rely upon being able to obtain information about the web server's directory structure by locating directories without default pages. In the scenario, the web server will display to the user a listing of the files in the directory being accessed. By having a default hosted application web page, the anonymous web user will not obtain directory browsing information or an error message that reveals the server type and version.

As a web server, tc Server can be vulnerable to enumeration techniques if steps are not taken to mitigate the vulnerability. Ensuring that every document directory has an "index.jsp" (or equivalent) file is one common sense approach to mitigating the vulnerability.

Web servers will often display error messages to client users displaying enough information to aid in the debugging of the error. The information given back in error messages may display the web server type, version, patches installed, plug-ins and modules installed, type of code being used by the hosted application, and any backends being used for data storage.

Information needed by an attacker to begin looking for possible vulnerabilities in a web server includes any information about the web server and plug-ins or modules being used. When debugging or trace information is enabled in a production web server, information about the web server, such as web server type, version, patches installed, plug-ins and modules installed, type of code being used by the hosted application, and any backends being used for data storage may be displayed. Since this information may be placed in logs and general messages during normal operation of the web server, an attacker does not need to cause an error condition to gain this information.

As a Tomcat derivative, tc Server can be configured to set the debugging level. By setting the debugging level to zero (0), no debugging information will be provided to a malicious user. This provides a layer of defense to vROps.

Information needed by an attacker to begin looking for possible vulnerabilities in a web server includes any information about the web server and plug-ins or modules being used. When debugging or trace information is enabled in a production web server, information about the web server, such as web server type, version, patches installed, plug-ins and modules installed, type of code being used by the hosted application, and any backends being used for data storage may be displayed. Since this information may be placed in logs and general messages during normal operation of the web server, an attacker does not need to cause an error condition to gain this information.

As a Tomcat derivative, tc Server can be configured to set the debugging level. By setting the debugging level to zero (0), no debugging information will be provided to a malicious user. This provides a layer of defense to vROps.

Leaving sessions open indefinitely is a major security risk. An attacker can easily use an already authenticated session to access the hosted application as the previously authenticated user. By closing sessions after a set period of inactivity, the web server can make certain that those sessions that are not closed through the user logging out of an application are eventually closed.

tc Server provides a session timeout parameter in the web.xml configuration file.

Remote access to the web server is any access that communicates through an external, non-organization-controlled network. Remote access can be used to access hosted applications or to perform management functions.

A web server can be accessed remotely and must be able to enforce remote access policy requirements or work in conjunction with enterprise tools designed to enforce policy requirements.

vRealize Operations can be configured with a variety of authentication sources. Site policies and procedures will dictate the appropriate authentication mechanism.

Remote access to the web server is any access that communicates through an external, non-organization-controlled network. Remote access can be used to access hosted applications or to perform management functions.

tc Server connections are managed by the Connector object class. By configuring external Connector objects to use the HTTPS scheme, vROps's information in flight will be protected.

In order to make certain that the logging mechanism used by the web server has sufficient storage capacity in which to write the logs, the logging mechanism needs to be able to allocate log record storage capacity.

The task of allocating log record storage capacity is usually performed during initial installation of the logging mechanism. The system administrator will usually coordinate the allocation of physical drive space with the web server administrator along with the physical location of the partition and disk. Refer to NIST SP 800-92 for specific requirements on log rotation and storage dependent on the impact of the web server.

It is critical for the appropriate personnel to be aware if a system is at risk of failing to process logs as required. Log processing failures include: software/hardware errors, failures in the log capturing mechanisms, and log storage capacity being reached or exceeded.

If log capacity were to be exceeded, then events subsequently occurring would not be recorded. Organizations must define a maximum allowable percentage of storage capacity serving as an alarming threshold (e.g., web server has exceeded 75% of log storage capacity allocated), at which time the web server or the logging mechanism the web server utilizes will provide a warning to the ISSO and SA at a minimum.

This requirement can be met by configuring the web server to utilize a dedicated log tool that meets this requirement.

If time stamps are not consistently applied and there is no common time reference, it is difficult to perform forensic analysis across multiple devices and log records.

Time stamps generated by the web server include date and time. Time is commonly expressed in Coordinated Universal Time (UTC), a modern continuation of Greenwich Mean Time (GMT), or local time with an offset from UTC.

Like all web servers, tc Server logs can be configured to produce a Common Log Format (CLF). The tc Server component known as an "AccessLogValve", which represents a component that can be inserted into the request processing pipeline to capture user interaction. The "Access Log Valve" creates log files in the same format as those created by standard web servers including GMT offset.

Without sufficient granularity of time stamps, it is not possible to adequately determine the chronological order of records.

Time stamps generated by the web server include date and time and must be to a granularity of one second.

Like all web servers, tc Server logs can be configured to produce a Common Log Format (CLF). The tc Server component known as an "AccessLogValve", which represents a component that can be inserted into the request processing pipeline to capture user interaction. The "Access Log Valve" should be configured to ensure that investigators have sufficient information to conduct an appropriate audit.

Without sufficient granularity of time stamps, it is not possible to adequately determine the chronological order of records.

Time stamps generated by the web server include date and time and must be to a granularity of one second.

Like all web servers, tc Server logs can be configured to produce a Common Log Format (CLF). The tc Server component known as an AccessLogValve, which represents a component that can be inserted into the request processing pipeline to capture user interaction. The Access Log Valve should be configured to ensure that investigators have sufficient information to conduct an appropriate audit.

A web server can be modified through parameter modification, patch installation, upgrades to the web server or modules, and security parameter changes. With each of these changes, there is the potential for an adverse effect such as a DoS, web server instability, or hosted application instability.

To limit changes to the web server and limit exposure to any adverse effects from the changes, files such as the web server application files, libraries, and configuration files must have permissions and ownership set properly to only allow privileged users access.

Web servers provide numerous processes, features, and functionalities that utilize TCP/IP ports. Some of these processes may be deemed unnecessary or too unsecure to run on a production system.

The web server must provide the capability to disable or deactivate network-related services that are deemed to be non-essential to the server mission, are too unsecure, or are prohibited by the PPSM CAL and vulnerability assessments.

An essential configuration file for tc Server is "catalina.properties". The ports that tc Server listens to will be configured in that file.

Web servers provide numerous processes, features, and functionalities that utilize TCP/IP ports. Some of these processes may be deemed unnecessary or too unsecure to run on a production system.

The web server must provide the capability to disable or deactivate network-related services that are deemed to be non-essential to the server mission, are too unsecure, or are prohibited by the PPSM CAL and vulnerability assessments.

An essential configuration file for tc Server is "catalina.properties". The ports that tc Server listens to will be configured in that file.

Cryptography is only as strong as the encryption modules/algorithms employed to encrypt the data.

Use of weak or untested encryption algorithms undermines the purposes of utilizing encryption to protect data.

NSA has developed Type 1 algorithms for protecting classified information. The Committee on National Security Systems (CNSS) National Information Assurance Glossary (CNSS Instruction No. 4009) defines Type 1 products as:

"Cryptographic equipment, assembly or component classified or certified by NSA for encrypting and decrypting classified and sensitive national security information when appropriately keyed. Developed using established NSA business processes and containing NSA-approved algorithms are used to protect systems requiring the most stringent protection mechanisms."

Although persons may have a security clearance, they may not have a "need-to-know" and are required to be separated from the information in question. The web server must employ NSA-approved cryptography to protect classified information from those individuals who have no "need-to-know" or when encryption of compartmentalized data is required by data classification.

An attacker has at least two reasons to stop a web server. The first is to cause a DoS, and the second is to put in place changes the attacker made to the web server configuration.

As a Tomcat derivative, tc Server uses a port (defaults to 8005) as a shutdown port. If enabled, a shutdown signal can be sent to tc Server through this port. To ensure availability, the shutdown port should be disabled.

An attacker has at least two reasons to stop a web server. The first is to cause a DoS, and the second is to put in place changes the attacker made to the web server configuration.

As a Tomcat derivative, tc Server uses a port (defaults to 8005) as a shutdown port. If enabled, a shutdown signal can be sent to tc Server through this port. To ensure availability, the shutdown port should be disabled.

Preventing the disclosure of transmitted information requires that the web server take measures to employ some form of cryptographic mechanism in order to protect the information during transmission. This is usually achieved through the use of Transport Layer Security (TLS).

Transmission of data can take place between the web server and a large number of devices/applications external to the web server. Examples are a web client used by a user, a backend database, an audit server, or other web servers in a web cluster.

tc Server connections are managed by the Connector object class. The Connector object can be configured to use a range of transport encryption methods. Many older transport encryption methods have been proven to be weak. vROps should be configured to use modern, secure forms of transport encryption.

The HTTP protocol is a stateless protocol. To maintain a session, a session identifier is used. The session identifier is a piece of data that is used to identify a session and a user. If the session identifier is compromised by an attacker, the session can be hijacked. By encrypting the session identifier, the identifier becomes more difficult for an attacker to hijack, decrypt, and use before the session has expired.

tc Server connections are managed by the Connector object class. The Connector object can be configured to use a range of transport encryption methods. Many older transport encryption methods have been proven to be weak. vROps should be configured to use modern, secure forms of transport encryption.

The HTTP protocol is a stateless protocol. To maintain a session, a session identifier is used. The session identifier is a piece of data that is used to identify a session and a user. If the session identifier is compromised by an attacker, the session can be hijacked. By encrypting the session identifier, the identifier becomes more difficult for an attacker to hijack, decrypt, and use before the session has expired.

tc Server connections are managed by the Connector object class. The Connector object can be configured to use a range of transport encryption methods. Many older transport encryption methods have been proven to be weak. vROps should be configured to use modern, secure forms of transport encryption.

A cookie can be read by client-side scripts easily if cookie properties are not set properly. By allowing cookies to be read by the client-side scripts, information such as session identifiers could be compromised and used by an attacker who intercepts the cookie. Setting cookie properties (i.e. HttpOnly property) to disallow client-side scripts from reading cookies better protects the information inside the cookie.

As a Tomcat derivative, tc Server contains a Context object, which represents a web application running within a particular virtual host. One of the configurable parameters of the Context object will prevent the tc Server cookies from being accessed by JavaScript from another site.

Cookies can be sent to a client using TLS/SSL to encrypt the cookies, but TLS/SSL is not used by every hosted application since the data being displayed does not require the encryption of the transmission. To safeguard against cookies, especially session cookies, being sent in plaintext, a cookie can be encrypted before transmission. To force a cookie to be encrypted before transmission, the cookie Secure property can be set.

As a Tomcat derivative, tc Server is based in part on the Java Servlet specification. Servlet 3.0 (Java EE 6) introduced a standard way to configure secure attribute for the session cookie, this can be done by applying the correct configuration in web.xml.

Cookies can be sent to a client using TLS/SSL to encrypt the cookies, but TLS/SSL is not used by every hosted application since the data being displayed does not require the encryption of the transmission. To safeguard against cookies, especially session cookies, being sent in plaintext, a cookie can be encrypted before transmission. To force a cookie to be encrypted before transmission, the cookie Secure property can be set.

As a Tomcat derivative, tc Server is based in part on the Java Servlet specification. Servlet 3.0 (Java EE 6) introduced a standard way to configure secure attribute for the session cookie, this can be done by applying the correct configuration in web.xml.

Transport Layer Security (TLS) is a required transmission protocol for a web server hosting controlled information. The use of TLS provides confidentiality of data in transit between the web server and client. FIPS 140-2 approved TLS versions must be enabled and non-FIPS-approved SSL versions must be disabled.

NIST SP 800-52 defines the approved TLS versions for government applications.

tc Server connections are managed by the Connector object class. The Connector object can be configured to use a range of transport encryption methods. Many older transport encryption methods have been proven to be weak. vROps should be configured to use the "sslEnabledProtocols" correctly to ensure that older, less secure forms of transport security are not used.

During the initial setup of a Transport Layer Security (TLS) connection to the web server, the client sends a list of supported cipher suites in order of preference. The web server will reply with the cipher suite it will use for communication from the client list. If an attacker can intercept the submission of cipher suites to the web server and place, as the preferred cipher suite, a weak export suite, the encryption used for the session becomes easy for the attacker to break, often within minutes to hours.

An essential configuration file for tc Server is "catalina.properties". Properly configured, tc Server will not provide the weaker, export ciphers.

During the initial setup of a Transport Layer Security (TLS) connection to the web server, the client sends a list of supported cipher suites in order of preference. The web server will reply with the cipher suite it will use for communication from the client list. If an attacker can intercept the submission of cipher suites to the web server and place, as the preferred cipher suite, a weak export suite, the encryption used for the session becomes easy for the attacker to break, often within minutes to hours.

An essential configuration file for tc Server is "catalina.properties". Properly configured, tc Server will not provide the weaker, export ciphers.

Information can be either unintentionally or maliciously disclosed or modified during reception, including, for example, during aggregation, at protocol transformation points, and during packing/unpacking. These unauthorized disclosures or modifications compromise the confidentiality or integrity of the information.

Protecting the confidentiality and integrity of received information requires that application servers take measures to employ approved cryptography in order to protect the information during transmission over the network. This is usually achieved through the use of Transport Layer Security (TLS), SSL VPN, or IPsec tunnel.

tc Server connections are managed by the Connector object class. The Connector object can be configured to use a range of transport encryption methods. Many older transport encryption methods have been proven to be weak. vROps should be configured to use the "sslEnabledProtocols" correctly to ensure that older, less secure forms of transport security are not used.

Security flaws with software applications are discovered daily. Vendors are constantly updating and patching their products to address newly discovered security vulnerabilities. Organizations (including any contractor to the organization) are required to promptly install security-relevant software updates (e.g., patches, service packs, and hot fixes). Flaws discovered during security assessments, continuous monitoring, incident response activities, or information system error handling must also be addressed expeditiously.

The web server will be configured to check for and install security-relevant software updates from an authoritative source within an identified time period from the availability of the update. By default, this time period will be every 24 hours.

VMware delivers product updates and patches regularly. It is crucial that system administrators coordinate installation of product updates with the site ISSO to ensure that updated and patched files are uploaded onto the system as soon as prescribed.

Security flaws with software applications are discovered daily. Vendors are constantly updating and patching their products to address newly discovered security vulnerabilities. Organizations (including any contractor to the organization) are required to promptly install security-relevant software updates (e.g., patches, service packs, and hot fixes). Flaws discovered during security assessments, continuous monitoring, incident response activities, or information system error handling must also be addressed expeditiously.

Organization-defined time periods for updating security-relevant software may vary based on a variety of factors including, for example, the security category of the information system or the criticality of the update (i.e., severity of the vulnerability related to the discovered flaw).

This requirement will apply to software patch management solutions used to install patches across the enclave and to applications themselves that are not part of that patch management solution. For example, many browsers today provide the capability to install their own patch software. Patch criticality, as well as system criticality will vary. Therefore, the tactical situations regarding the patch management process will also vary. This means that the time period used must be a configurable parameter. Time frames for application of security-relevant software updates may be dependent upon the Information Assurance Vulnerability Management (IAVM) process.

The application will be configured to check for and install security-relevant software updates within an identified time period from the availability of the update. The specific time period will be defined by an authoritative source (e.g., IAVM, CTOs, DTMs, and STIGs).