Linux distributions
TMA-ROCKY9-7.2.6
Ensure no duplicate user names exist
MediumLevel 1Automatedlinux
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 username.
How it is checked
Audit method: Shell command
shell
alt0() { o=$(bash -c '#!/usr/bin/env bash
{
while read -r l_count l_user; do
if [ "$l_count" -gt 1 ]; then
echo -e "Duplicate User: \"$l_user\" Users: \"$(awk -F: '"'"'($1 == n) { print $1 }'"'"' n=$l_user /etc/passwd | xargs)\""
fi
done < <(cut -f1 -d":" /etc/passwd | sort -n | uniq -c)
}' 2>&1); [ -z "$o" ] || { echo "step1: $o" | head -c 300; return 1; }; }; if alt0; then echo compliant; fi- Expected output
compliant
How it is fixed
Fix method: Guidance or infrastructure patch
Based on the Audit Procedure output, for each duplicated user name, determine which entry is correct and make each user name unique. Use vipw to safely edit the user database and either remove the redundant entry or rename it to a unique user name: # vipw File ownerships will reflect the change automatically as long as each account has a unique UID.
Properties
- Operating systems
- rocky-9
- Tags
- cis-convertedlinux
- Reference
- CIS Rocky Linux 9 Benchmark v3.0.0 - 7.2.6
Check this host
Run this on a machine you are allowed to audit. The scan is read-only.
shell
tmaegis scan --target linux