What changed in Anduril NixOS STIG V1R3V1R3 changes

Anduril NixOS STIG V1R3 (2026-09-30) replaced V1R2 (2025-10-01): 14 checks updated. It has 103 checks, against 103 in V1R2.

  • 0 added
  • 0 removed
  • 14 updated

Updated fields: Discussion 11Title 6Check text 5Fix text 5

Updated in V1R3 (14)

V-268082CAT IINixOS must be configured to display the Standard Mandatory DoW Notice and Consent Banner before granting local or remote access to the system via a command line user logon.Title, Check text, Fix text, Discussion

Title

NixOS must be configured to display the Standard Mandatory DODDoW Notice and Consent Banner before granting local or remote access to the system via a command line user logon.

Check text

Verify that NixOS displays the Standard Mandatory DODDoW Notice and Consent Banner before granting access to the system via a command line user logon with the following command: $ tail -n+3 /etc/issue You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. If the /etc/issue does not contain a banner, or the banner does not match the Standard Mandatory DODDoW Notice and Consent Banner, this is a finding.

Fix text

Configure NixOS to display the Standard Mandatory DODDoW Notice and Consent Banner before granting access to the system via a command line. Update the NixOS config, typically stored either in /etc/nixos/configuration.nix or /etc/nixos/flake.nix: services.getty.helpLine = '' You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. ''; Rebuild and switch to the new NixOS configuration: $ sudo nixos-rebuild switch

Discussion

Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. System use notifications are required only for access via logon interfaces with human users and are not required when such human interfaces do not exist. The banner must be formatted in accordance with applicable DODDoW policy. Use the following verbiage for operating systems that can accommodate banners of 1300 characters: "You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details." Use the following verbiage for operating systems that have severe limitations on the number of characters that can be displayed in the banner: "I've read & consent to terms in IS user agreement." 2) Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. System use notifications are required only for access via logon interfaces with human users and are not required when such human interfaces do not exist.

V-268083CAT IINixOS must be configured to display the Standard Mandatory DoW Notice and Consent Banner before granting local or remote access to the system via an SSH logon.Title, Check text, Fix text, Discussion

Title

NixOS must be configured to display the Standard Mandatory DODoW Notice and Consent Banner before granting local or remote access to the system via an SSH logon.

Check text

Verify the operating system displays the Standard Mandatory DODDoW Notice and Consent Banner before granting access to the system via a ssh logon with the following commands: $ grep Banner /etc/ssh/sshd_config $ cat /nix/store/&lthash>-ssh_banner You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. If the "Banner" is not configured in the sshd_config, or the banner does not match the Standard Mandatory DODDoW Notice and Consent Banner, this is a finding.

Fix text

Configure NixOS to display the Standard Mandatory DODDoW Notice and Consent Banner before granting access to the system via openssh. Update the NixOS config, typically stored either in "/etc/nixos/configuration.nix" or "/etc/nixos/flake.nix": services.openssh.banner = '' You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. ''; Rebuild and switch to the new NixOS configuration: $ sudo nixos-rebuild switch

Discussion

Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. System use notifications are required only for access via logon interfaces with human users and are not required when such human interfaces do not exist. The banner must be formatted in accordance with applicable DODDoW policy. Use the following verbiage for operating systems that can accommodate banners of 1300 characters: "You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details." Use the following verbiage for operating systems that have severe limitations on the number of characters that can be displayed in the banner: "I've read & consent to terms in IS user agreement." 2) Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. System use notifications are required only for access via logon interfaces with human users and are not required when such human interfaces do not exist.

V-268084CAT IINixOS must be configured to display the Standard Mandatory DoW Notice and Consent Banner before granting local or remote access to the system via a graphical user logon.Title, Check text, Fix text, Discussion

Title

NixOS must be configured to display the Standard Mandatory DODDoW Notice and Consent Banner before granting local or remote access to the system via a graphical user logon.

Check text

Verify NixOS displays the Standard Mandatory DODDoW Notice and Consent Banner before granting access to the system via the graphical user logon with the following command: $ DCONF_PROFILE=gdm dconf read "/org/gnome/login-screen/banner-message-text" You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details. If the dconf tool does not return a banner, or the banner does not match the Standard Mandatory DODDoW Notice and Consent Banner, this is a finding.

Fix text

Configure NixOS to display the Standard Mandatory DODDoW Notice and Consent Banner before granting access to the system via a graphical user logon. Update the NixOS config, typically stored either in "/etc/nixos/configuration.nix" or "/etc/nixos/flake.nix": services.xserver.displayManager.gdm.banner = "You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions:1n-The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations.1n-At any time, the USG may inspect and seize data stored on this IS.1n-Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose.1n-This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy.1n-Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details."; Rebuild and switch to the new NixOS configuration: $ sudo nixos-rebuild switch

Discussion

Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. System use notifications are required only for access via logon interfaces with human users and are not required when such human interfaces do not exist. The banner must be formatted in accordance with applicable DODDoW policy. Use the following verbiage for operating systems that can accommodate banners of 1300 characters: "You are accessing a U.S. Government (USG) Information System (IS) that is provided for USG-authorized use only. By using this IS (which includes any device attached to this IS), you consent to the following conditions: -The USG routinely intercepts and monitors communications on this IS for purposes including, but not limited to, penetration testing, COMSEC monitoring, network operations and defense, personnel misconduct (PM), law enforcement (LE), and counterintelligence (CI) investigations. -At any time, the USG may inspect and seize data stored on this IS. -Communications using, or data stored on, this IS are not private, are subject to routine monitoring, interception, and search, and may be disclosed or used for any USG-authorized purpose. -This IS includes security measures (e.g., authentication and access controls) to protect USG interests--not for your personal benefit or privacy. -Notwithstanding the above, using this IS does not constitute consent to PM, LE or CI investigative searching or monitoring of the content of privileged communications, or work product, related to personal representation or services by attorneys, psychotherapists, or clergy, and their assistants. Such communications and work product are private and confidential. See User Agreement for details." Use the following verbiage for operating systems that have severe limitations on the number of characters that can be displayed in the banner: "I've read & consent to terms in IS user agreement." 2) Display of a standardized and approved use notification before granting access to the operating system ensures privacy and security notification verbiage used is consistent with applicable federal laws, Executive Orders, directives, policies, regulations, standards, and guidance. System use notifications are required only for access via logon interfaces with human users and are not required when such human interfaces do not exist. Satisfies: SRG-OS-000023-GPOS-00006, SRG-OS-000228-GPOS-00088

V-268088CAT IINixOS must monitor remote access methods.Discussion

Discussion

Remote access services, such as those providing remote access to network devices and information systems, which lack automated monitoring capabilities, increase risk and make remote user access management difficult at best. Remote access is access to DODDoW nonpublic information systems by an authorized user (or an information system) communicating through an external, nonnonorganization-organization-controlled network. Remote access methods include, for example, dial-up, broadband, and wireless. Automated monitoring of remote access sessions allows organizations to detect cyberattacks and also ensure ongoing compliance with remote access policies by auditing connection activities of remote access capabilities, such as Remote Desktop Protocol (RDP), on a variety of information system components (e.g., servers, workstations, notebook computers, smartphones, and tablets).

V-268089CAT INixOS must implement DoW-approved encryption to protect the confidentiality of remote access sessions.Title, Discussion

Title

NixOS must implement DODoW-approved encryption to protect the confidentiality of remote access sessions.

Discussion

Without confidentiality protection mechanisms, unauthorized individuals may gain access to sensitive information via a remote access session. Remote access is access to DODDoW nonpublic information systems by an authorized user (or an information system) communicating through an external, nonorganization-controlled network. Remote access methods include, for example, dial-up, broadband, and wireless. Encryption provides a means to secure the remote connection to prevent unauthorized access to the data traversing the remote access connection (e.g., RDP), thereby providing a degree of confidentiality. The encryption strength of a mechanism is selected based on the security categorization of the information. Satisfies: SRG-OS-000033-GPOS-00014, SRG-OS-000250-GPOS-00093, SRG-OS-000394-GPOS-00174

V-268092CAT IINixOS must enable auditing of processes that start prior to the audit daemon.Discussion

Discussion

Without the capability to generate audit records, it would be difficult to establish, correlate, and investigate the events relating to an incident or identify those responsible for one. If auditing is enabled late in the startup process, the actions of some startup processes may not be audited. Some audit systems also maintain state information only available if auditing is enabled before a given process is created. Audit records can be generated from various components within the information system (e.g., module or policy filter). The list of audited events is the set of events for which audits are to be generated. This set of events is typically a subset of the list of all events for which the system is capable of generating audit records. DODDoW has defined the list of events for which NixOS will provide an audit record generation capability as the following: 1) Successful and unsuccessful attempts to access, modify, or delete privileges, security objects, security levels, or categories of information (e.g., classification levels); 2) Access actions, such as successful and unsuccessful logon attempts, privileged activities or other system-level access, starting and ending time for user access to the system, concurrent logons from different workstations, successful and unsuccessful accesses to objects, all program initiations, and all direct access to the information system; 3) All account creations, modifications, disabling, and terminations; and 4) All kernel module load, unload, and restart actions.

V-268124CAT IINixOS, for PKI-based authentication, must validate certificates by constructing a certification path (which includes status information) to an accepted trust anchor.Check text, Fix text

Check text

Verify NixOS only allows the use of DODDoW PKI-established certificate authorities by running the following: $ openssl x509 -text -in /etc/sssd/pki/sssd_auth_ca_db.pem Certificate: Data: Version: 3 (0x2) Serial Number: 1 (0x1) Signature Algorithm: sha256WithRSAEncryption Issuer: C = US, O = U.S. Government, OU = DODDoW, OU = PKI, CN = DOD Root CA 3 Validity Not Before: Mar 20 18:46:41 2012 GMT Not After : Dec 30 18:46:41 2029 GMT Subject: C = US, O = U.S. Government, OU = DODDoW, OU = PKI, CN = DOD Root CA 3 Subject Public Key Info: Public Key Algorithm: rsaEncryption If the root CA file is not a DODDoW-issued certificate with a valid date and installed in the /etc/sssd/pki/sssd_auth_ca_db.pem location, this is a finding.

Fix text

Configure NixOS to authenticate using DODDoW's root CA. Add the following Nix code to the NixOS Configuration, usually located in "/etc/nixos/configuration.nix" or "/etc/nixos/flake.nix": services.sssd.enable = true; environment.etc."sssd/pki/sssd_auth_ca_db.pem".source = let certzip = pkgs.fetchzip { url = "https://dl.dod.cyber.mil/wp-content/uploads/pki-pke/zip/unclass-certificates_pkcs7_v5-6_dod6_DoW.zip"; sha256 = "sha256-iwwJRXCnONk/LFddQlwy8KX9e9kVXW/QWDnX5qZFZjc="; }; in "${certzip}/DOD_PKE_CA_chainDoW_PKE_CA_chain.pem"; Rebuild and switch to the new NixOS configuration: $ sudo nixos-rebuild switch

V-268133CAT IINixOS must enforce a 180-day maximum password lifetime restriction.Title, Check text, Fix text

Title

NixOS must enforce a 6180-day maximum password lifetime restriction.

Check text

Verify NixOS enforces a 60180-day maximum password lifetime for new user accounts by running the following command: $ grep PASS_MAX_DAYS /etc/login.defs PASS_MAX_DAYS 60180 If the "PASS_MAX_DAYS" parameter value is less than 60180 or commented out, this is a finding.

Fix text

Configure NixOS operating system to enforce a 60180-day maximum password lifetime. Add the following Nix code to the NixOS Configuration, usually located in /etc/nixos/configuration.nix or /etc/nixos/flake.nix: security.loginDefs.settings.PASS_MAX_DAYS = "60180"; Rebuild and switch to the new NixOS configuration: $ sudo nixos-rebuild switch

V-268136CAT IINixOS must use multifactor authentication for network access to privileged accounts.Discussion

Discussion

Without the use of multifactor authentication, the ease of access to privileged functions is greatly increased. Multifactor authentication requires using two or more factors to achieve authentication. Factors include: 1) something a user knows (e.g., password/PIN); 2) something a user has (e.g., cryptographic identification device, token); and 3) something a user is (e.g., biometric). A privileged account is defined as an information system account with authorizations of a privileged user. Network access is defined as access to an information system by a user (or a process acting on behalf of a user) communicating through a network (e.g., local area network, wide area network, or the internet). The DODDoW common access card (CAC) with DODDoW-approved Public Key Infrastructure (PKI) is an example of multifactor authentication. Satisfies: SRG-OS-000105-GPOS-00052, SRG-OS-000106-GPOS-00053, SRG-OS-000107-GPOS-00054, SRG-OS-000108-GPOS-00055

V-268140CAT IIA sticky bit must be set on all NixOS public directories to prevent unauthorized and unintended information transferred via shared system resources.Discussion

Discussion

Preventing unauthorized information transfers mitigates the risk of information, including encrypted representations of information, produced by the actions of prior users/roles (or the actions of processes acting on behalf of prior users/roles) from being available to any current users/roles (or current processes) that obtain access to shared system resources (e.g., registers, main memory, hard disks) after those resources have been released back to information systems. The control of information in shared resources is also commonly referred to as object reuse and residual information protection. This requirement generally applies to the design of an information technology product, but it can also apply to the configuration of particular information system components that are, or use, such products. This can be verified by acceptance/validation processes in DODDoW or other government agencies. There may be shared resources with configurable protections (e.g., files in storage) that may be assessed on specific information system components.

V-268149CAT IINixOS must, for networked systems, compare internal information system clocks at least every 24 hours with a server which is synchronized to one of the redundant United States Naval Observatory (USNO) time servers, or a time server designated for the appropriate DoW network (NIPRNet/SIPRNet), and/or the Global Positioning System (GPS).Title

Title

NixOS must, for networked systems, compare internal information system clocks at least every 24 hours with a server which is synchronized to one of the redundant United States Naval Observatory (USNO) time servers, or a time server designated for the appropriate DODDoW network (NIPRNet/SIPRNet), and/or the Global Positioning System (GPS).

V-268154CAT INixOS must prevent the installation of patches, service packs, device drivers, or operating system components without verification they have been digitally signed using a certificate that is recognized and approved by the organization.Discussion

Discussion

Changes to any software components can have significant effects on the overall security of the operating system. This requirement ensures the software has not been tampered with and that it has been provided by a trusted vendor. Accordingly, patches, service packs, device drivers, or operating system components must be signed with a certificate recognized and approved by the organization. Verifying the authenticity of the software prior to installation validates the integrity of the patch or upgrade received from a vendor. This ensures the software has not been tampered with and that it has been provided by a trusted vendor. Self-signed certificates are disallowed by this requirement. The operating system should not have to verify the software again. This requirement does not mandate DODDoW certificates for this purpose; however, the certificate used to verify the software must be from an approved certificate authority (CA).

V-268175CAT IINixOS must employ approved cryptographic hashing algorithms for all stored passwords.Discussion

Discussion

Unapproved mechanisms that are used for authentication to the cryptographic module are not verified and therefore cannot be relied upon to provide confidentiality or integrity, and DODDoW data may be compromised. Operating systems using encryption are required to use FIPS-compliant mechanisms for authenticating to cryptographic modules. FIPS 140-3 is the current standard for validating that mechanisms used to access cryptographic modules use authentication that meets DODDoW requirements. This allows for Security Levels 1, 2, 3, or 4 for use on a general purpose computing system.

V-268177CAT IINixOS must implement multifactor authentication for remote access to privileged accounts in such a way that one of the factors is provided by a device separate from the system gaining access.Discussion

Discussion

Using an authentication device, such as a common access card (CAC) or token that is separate from the information system, ensures that even if the information system is compromised, that compromise will not affect credentials stored on the authentication device. Multifactor solutions that require devices separate from information systems gaining access include, for example, hardware tokens providing time-based or challenge-response authenticators and smart cards such as the U.S. Government Personal Identity Verification (PIV) card and the DODDoW Common Access Card (CAC). A privileged account is defined as an information system account with authorizations of a privileged user. Remote access is access to DODDoW nonpublic information systems by an authorized user (or an information system) communicating through an external, nonorganization-controlled network. Remote access methods include, for example, dial-up, broadband, and wireless. This requirement only applies to components where this is specific to the function of the device or has the concept of an organizational user (e.g., VPN, proxy capability). This does not apply to authentication for the purpose of configuring the device itself (management). This requires further clarification from NIST. Satisfies: SRG-OS-000375-GPOS-00160, SRG-OS-000068-GPOS-00036, SRG-OS-000376-GPOS-00161, SRG-OS-000377-GPOS-00162, SRG-OS-000705-GPOS-00150

How these changes are found

Checks are matched across the two releases by V-number. A check counts as updated when DISA gave it a new rule revision (the r number in its SV-…_rule id) and its title, severity, check text, fix text, discussion, CCIs or other fields changed — the same comparison STIG Compare makes. Added checks are new V-numbers; removed checks are V-numbers V1R3 no longer has.

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