.. / CVE-2022-31214

Exploit for Firejail 0.9.68 Privilege Context Switching - Local Privilege Escalation (CVE-2022-31214)

Description:

A Privilege Context Switching issue was discovered in join.c in Firejail 0.9.68. By crafting a bogus Firejail container that is accepted by the Firejail setuid-root program as a join target, a local attacker can enter an environment in which the Linux user namespace is still the initial user namespace, the NO_NEW_PRIVS prctl is not activated, and the entered mount namespace is under the attacker’s control. In this way, the filesystem layout can be adjusted to gain root privileges through execution of available setuid-root binaries such as su or sudo.

Proof of Concept

PoC exploit

Try the exploit in a lab environment:

Lab Machine Link
Hack The Box Sandworm Go to Practice

References:

https://nvd.nist.gov/vuln/detail/CVE-2022-31214
https://firejail.wordpress.com/download-2/release-notes/
https://lists.debian.org/debian-lts-announce/2022/06/msg00023.html
https://www.openwall.com/lists/oss-security/2022/06/08/10
https://lists.debian.org/debian-security-announce/2022/msg00135.html