Vulnerability Discussion

To ensure accountability and prevent unauthenticated access, interactive users must be identified and authenticated to prevent potential misuse and compromise of the system.

Satisfies: SRG-OS-000104-GPOS-00051, SRG-OS-000121-GPOS-00062, SRG-OS-000042-GPOS-00020

Check

Verify Amazon Linux 2023 contains no duplicate UIDs for interactive users with the following command:

$ sudo awk -F ":" 'list[$3]++{print $1, $3}' /etc/passwd

If output is produced and the accounts listed are interactive user accounts, this is a finding.

Fix

Configure Amazon Linux 2023 to contain no duplicate UIDs for interactive users.

Edit the file "/etc/passwd" and provide each interactive user account that has a duplicate UID with a unique UID.