CVE-2026-53129
What it is
In the Linux kernel, the following vulnerability has been resolved: fs/mbcache: cancel shrink work before destroying the cache mb_cache_destroy() calls shrinker_free() and then frees all cache entries and the cache itself, but it does not cancel the pending c_shrink_work work item first. If mb_cache_entry_create() schedules c_shrink_work via schedule_work() and the work item is still pending or running when mb_cache_destroy() runs, mb_cache_shrink_worker() will access the cache after its memory has been freed, causing a use-after-free. This is only reachable by a privileged user (root or CAP_SYS_ADMIN) who can trigger the last put of a mounted ext2/ext4/ocfs2 filesystem. Cancel the work item with cancel_work_sync() before calling shrinker_free(), ensuring the worker has finished and will not be rescheduled before the cache is torn down.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Modified
Affected
- Linux Kernel < 6.12.91
- Linux Kernel < 6.18.33
- Linux Kernel < 7.0.10
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Fix and advisories
- https://git.kernel.org/stable/c/0e4eff315d799f5842b95872199b0f0fb8ef5f51
- https://git.kernel.org/stable/c/a88d39a74a208e197c03bffaa2df34de732af19f
- https://git.kernel.org/stable/c/b25fd3523bef88fb7ffd4c5b63bbe9c08f73bb4c
- https://git.kernel.org/stable/c/d227786ab1119669df4dc333a61510c52047cce4
References
- https://git.kernel.org/stable/c/0e4eff315d799f5842b95872199b0f0fb8ef5f51
- https://git.kernel.org/stable/c/40148c615687c1692712e50a6de53d62dfbfc20f
- https://git.kernel.org/stable/c/a88d39a74a208e197c03bffaa2df34de732af19f
- https://git.kernel.org/stable/c/b25fd3523bef88fb7ffd4c5b63bbe9c08f73bb4c
- https://git.kernel.org/stable/c/cbdd6f0fb19a0ce8a013acd80ac87a62f57fa20d
- https://git.kernel.org/stable/c/d227786ab1119669df4dc333a61510c52047cce4