Description
Firejail before 0.9.44.4 and 0.9.38.x LTS before 0.9.38.8 LTS does not consider the .Xauthority case during its attempt to prevent accessing user files with an euid of zero, which allows local users to conduct sandbox-escape attacks via vectors involving a symlink and the --private option.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | firejail | 0.9.44.2-3 | — |
| Debian 13 | firejail | 0.9.44.2-3 | — |
| Debian 12 | firejail | 0.9.44.2-3 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | firejail | 0.9.38-1ubuntu0.1 | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | firejail | 0.9.66-1.2 | openSUSE-SU-2024:10759-1 |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
Exploit-DB 1
- Firejail < 0.9.44.4 / < 0.9.38.8 LTS - Local Sandbox Escape EDB-43359 · local · Jan 4, 2017
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Advisories 1
- openSUSE-SU-2024:10759-1 firejail-0.9.66-1.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026