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Least Privilege: Reconcile the sudo Group

MediumLinux Security20-25 min
The brief

Privilege creep: over time, extra accounts were added to the sudo group and never removed. Security signed off on an approved administrator list — /root/policy/approved-admins.txt, one username per line — and nobody else should hold sudo. Reconcile reality against policy: record every current sudo-group member who is NOT on the approved list in the file /root/answers/unauthorized.txt (usernames only, one per line), then remove exactly those from the sudo group, leaving the approved admins' access intact. (Least privilege — maps to NIST AC-6 / AC-2 and 800-171 3.1.5.)

What you'll do
  • Compare the sudo group's members against /root/policy/approved-admins.txt
  • Record the unauthorized sudo members to /root/answers/unauthorized.txt
  • Remove exactly the unauthorized members, keeping every approved admin in sudo

Hands-on lab: you work on a real Linux box in your browser, graded on the machine's actual state.