cyberstrikeus 13.11 Check Groups in /etc/passwd (Scored)
Profile Applicability
- Level 1
Description
Over time, system administration errors and changes can lead to groups being defined in /etc/passwd but not in /etc/group.
Rationale
Groups defined in the /etc/passwd file but not in the /etc/group file pose a threat to system security since group permissions are not properly managed.
Audit Procedure
Using Command Line
Create a script as shown below and run it:
#!/bin/bash
for i in $(cut -s -d: -f4 /etc/passwd | sort -u ); do
grep -q -P "^.*?:[^:]*:$i:" /etc/group
if [ $? -ne 0 ]; then
echo "Group $i is referenced by /etc/passwd but does not exist in /etc/group"
fi
done
Expected Result
No output should be returned. Any output indicates groups referenced in /etc/passwd that do not exist in /etc/group.
Remediation
Using Command Line
Analyze the output of the Audit step above and perform the appropriate action to correct any discrepancies found.
Default Value
All default system groups are properly defined in both /etc/passwd and /etc/group.
References
- CIS Ubuntu 12.04 LTS Server Benchmark v1.1.0
Profile
Level 1 - Scored