Title

GIDs reserved for system accounts must not be assigned to non-system groups. (Cat II impact)

Discussion

Reserved GIDs are typically used by system software packages. If non-system groups have GIDs in this range, they may conflict with system software, possibly leading to the group having permissions to modify system files.

Check Content

Confirm all accounts with a GID of 499 and below are used by a system account. Procedure: List all the users with a GID of 0-499. # awk -F: '$4 <= 499 {printf "%15s:%4s\n", $1, $4}' /etc/passwd | sort -n -t: -k2 If a GID reserved for system accounts (0 - 499) is used by a non-system account, this is a finding.

Fix Text

Change the primary group GID numbers for non-system accounts with reserved primary group GIDs (those less or equal to 499).

Additional Identifiers

Rule ID: SV-44826r1_rule

Vulnerability ID: V-780

Group Title: GEN000360

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.