CVE-2021-26910
Publication date 8 February 2021
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
Firejail before 0.9.64.4 allows attackers to bypass intended access restrictions because there is a TOCTOU race condition between a stat operation and an OverlayFS mount operation.
From the Ubuntu Security Team
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.
Status
Package | Ubuntu Release | Status |
---|---|---|
firejail | 24.10 oracular |
Not affected
|
24.04 LTS noble |
Not affected
|
|
22.04 LTS jammy |
Not affected
|
|
20.04 LTS focal |
Fixed 0.9.62-3ubuntu0.1
|
|
18.04 LTS bionic |
Needs evaluation
|
|
16.04 LTS xenial |
Needs evaluation
|
|
14.04 LTS trusty | Not in release |
Severity score breakdown
Parameter | Value |
---|---|
Base score | 7.0 · High |
Attack vector | Local |
Attack complexity | High |
Privileges required | Low |
User interaction | None |
Scope | Unchanged |
Confidentiality | High |
Integrity impact | High |
Availability impact | High |
Vector | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
References
Related Ubuntu Security Notices (USN)
- USN-5141-1
- Firejail vulnerability
- 11 November 2021
Other references
- https://www.openwall.com/lists/oss-security/2021/02/08/5
- https://unparalleled.eu/publications/2021/advisory-unpar-2021-0.txt
- https://unparalleled.eu/blog/2021/20210208-rigged-race-against-firejail-for-local-root/
- http://www.openwall.com/lists/oss-security/2021/02/09/1
- https://github.com/netblue30/firejail/commit/97d8a03cad19501f017587cc4e47d8418273834b
- https://github.com/netblue30/firejail/releases/tag/0.9.64.4
- https://www.cve.org/CVERecord?id=CVE-2021-26910