TMA-COS-6.2.18
Ensure no duplicate user names exist
Description
Although the useradd program will not let you create a duplicate user name, it is possible for an administrator to manually edit the /etc/passwd file and change the user name. If a user is assigned a duplicate user name, it will create and have access to files with the first UID for that username in /etc/passwd . For example, if "test4" has a UID of 1000 and a subsequent "test4" entry has a UID of 2000, logging in as "test4" will use UID 1000. Effectively, the UID is shared, which is a security problem.
How it is checked
Audit method: Shell command
cut -d: -f1 /etc/passwd | sort | uniq -d | grep -q . && echo noncompliant || echo compliant- Expected output
compliant
How it is fixed
Fix method: Guidance or infrastructure patch
Based on the results of the audit script, establish unique user names for the users. File ownerships will automatically reflect the change as long as the users have unique UIDs.
Properties
- Operating systems
- Any
- Tags
- container-optimized-oscos
- Reference
- CIS Google Container-Optimized OS Benchmark v1.2.0 - 6.2.18 Ensure no duplicate user names exist
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
tmaegis scan --target cos