Undo the Bad Commit

A commit added a security backdoor — undo it cleanly.

A intermediate Git challenge worth 10 points. Solve it hands-on in a real Git environment in your browser - no local setup, no fake shells.

The Challenge

Scenario: The repo in /tmp/site has two commits. The last one sneaked DEBUG_BACKDOOR=on into config.txt.

Tasks:

• Undo the last commit so config.txt no longer contains DEBUG_BACKDOOR
• Keep the real setting (port=8080)
• Use git revert (safe on shared history) or git reset — your choice

Commands to learn: git log, git revert, git reset

Run check when done.