SV-39099r1: The /etc/resolv.conf file must be group-owned by bin, sys, or system. | AIX 6.1 SECURITY TECHNICAL IMPLEMENTATION GUIDE

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Assessment Title

Rule Text

The /etc/resolv.conf file must be group-owned by bin, sys, or system.

Description

Discussion Text

The resolv.conf (or equivalent) file configures the system's DNS resolver. DNS is used to resolve host names to IP addresses. If DNS configuration is modified maliciously, host name resolution may fail or return incorrect information. DNS may be used by a variety of system security functions, such as time synchronization, centralized authentication, and remote system logging.

How this relates to the STIG checklist: STIG vs SCAP benchmark.

IA Controls

NIST SP 800-53

Not mappedCCI-000225

Additional Details

Responsibility

System Administrator

IA Controls

ECLP-1

References

DPMS Target AIX 6.1 DISA DPMS Target AIX 6.1 2176

SCC Automation Reference

The reconstructed evaluation script behind this rule's OVAL check(s) — every module a compound check combines, with this rule's own concrete values and DISA's SCC tool's real per-module mechanism curated from static teardown of SCC releases.

#!/bin/bash
# Reconstructed from oval:mil.disa.fso.aix11:def:80
# The /etc/resolv.conf file must be group-owned by bin, sys, or system.
# Per-module read mechanism curated from static teardown of DISA's SCC tool
# (SCAP Compliance Checker) -- see the SCC Automation Reference above.

# Test group of /etc/resolv.conf is root
# file_object (file_test)
test_1() {
  [ "$(stat -c '%g' '/etc/resolv.conf')" -eq 0 ]
}
# Test existence of group bin
# textfilecontent54_object (textfilecontent54_test)
test_2() {
  grep -Pq '^bin:[^:]*:([0-9]+):' '/etc/group' &>/dev/null
}
# Test group of /etc/resolv.conf is bin
# file_object (file_test)
test_3() {
  [ "$(stat -c '%g' '/etc/resolv.conf')" = "$(sed -En 's/^bin:[^:]*:([0-9]+):/\1/p' '/etc/group')" ]
}
# Test existence of group sys
# textfilecontent54_object (textfilecontent54_test)
test_4() {
  grep -Pq '^sys:[^:]*:([0-9]+):' '/etc/group' &>/dev/null
}
# Test group of /etc/resolv.conf is sys
# file_object (file_test)
test_5() {
  [ "$(stat -c '%g' '/etc/resolv.conf')" = "$(sed -En 's/^sys:[^:]*:([0-9]+):/\1/p' '/etc/group')" ]
}
# Test existence of group system
# textfilecontent54_object (textfilecontent54_test)
test_6() {
  grep -Pq '^system:[^:]*:([0-9]+):' '/etc/group' &>/dev/null
}
# Test group of /etc/resolv.conf is system
# file_object (file_test)
test_7() {
  [ "$(stat -c '%g' '/etc/resolv.conf')" = "$(sed -En 's/^system:[^:]*:([0-9]+):/\1/p' '/etc/group')" ]
}

if ( test_1 || ( test_2 && test_3 ) || ( test_4 && test_5 ) || ( test_6 && test_7 ) ); then
  echo "PASS"
else
  echo "FAIL"
fi

Assessment Script Powered by AISandbox-executed

A standalone Shell script to assess this control automatically. Review before running it in your environment.

Syntax-checked and actually executed in an isolated sandbox (not the real system this checks) — confirmed to run without errors.

#!/bin/sh
# oval:mil.disa.fso.aix11:def:80
if [ ! -f "/etc/resolv.conf" ]; then echo "PASS"; exit 0; fi
if [ $(stat -c "%G" /etc/resolv.conf) = "bin" ] || [ $(stat -c "%G" /etc/resolv.conf) = "sys" ] || [ $(stat -c "%G" /etc/resolv.conf) = "system" ]; then echo "PASS"; exit 0; fi
echo "FAIL"; exit 1

Remediation

Change the group owner of the /etc/resolv.conf file to bin, sys, or system.

Procedure:
# chgrp system /etc/resolv.conf