Ubuntu Security Notice 5141-1 - Roman Fiedler discovered that a race condition existed in Firejail when using OverlayFS to prevent writes to the underlying file system. A local attacker could use this to gain administrative privileges. Note: this update disables support for OverlayFS in Firejail.
de9ac90127621c56848f354ec0b711d244e2e154a3857da22e4ef5b089d14623
==========================================================================
Ubuntu Security Notice USN-5141-1
November 11, 2021
firejail vulnerability
==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 20.04 LTS
Summary:
Firejail could be made to overwrite files as the administrator.
Software Description:
- firejail: Application sandbox
Details:
Roman Fiedler discovered that a race condition existed in Firejail
when using OverlayFS to prevent writes to the underlying file system. A
local attacker could use this to gain administrative privileges. Note:
this update disables support for OverlayFS in Firejail.
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 20.04 LTS:
firejail 0.9.62-3ubuntu0.1
In general, a standard system update will make all the necessary changes.
References:
https://ubuntu.com/security/notices/USN-5141-1
CVE-2021-26910
Package Information:
https://launchpad.net/ubuntu/+source/firejail/0.9.62-3ubuntu0.1