CVE-2016-2853
Description
The aufs module for the Linux kernel 3.x and 4.x does not properly restrict the mount namespace, which allows local users to gain privileges by mounting an aufs filesystem on top of a FUSE filesystem, and then executing a crafted setuid program.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
Exploits
Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.
Exploit-DB
AUFS (Ubuntu 15.10) - 'allow_userns' Fuse/Xattr User Namespaces Privilege Escalation
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | bookworm | fixed | 3.18-1~exp1 |
| debian | bullseye | fixed | 3.18-1~exp1 |
| debian | forky | fixed | 3.18-1~exp1 |
| debian | sid | fixed | 3.18-1~exp1 |
| debian | trixie | fixed | 3.18-1~exp1 |
| linux-kernel | affected | |
References
- http://www.halfdog.net/Security/2016/AufsPrivilegeEscalationInUserNamespaces/
- http://www.openwall.com/lists/oss-security/2016/02/24/9
- http://www.openwall.com/lists/oss-security/2021/10/18/1
- http://www.securityfocus.com/bid/96839
- https://sourceforge.net/p/aufs/mailman/message/34864744/
- https://security-tracker.debian.org/tracker/CVE-2016-2853
CWEs
CWE-269
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.