fs/mbcache: cancel shrink work before destroying the cache
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 4 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 4.6 and later | 6.1.191, 6.6.160, 6.12.91, 6.18.33, 7.0.10, 7.1 | Patch available | CNA |
- Linux VendorLinux Affected 4.6 and later Fixed in 6.1.191, 6.6.160, 6.12.91, 6.18.33, 7.0.10, 7.1 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 4.6 to before 6.12.91; 6.13 to before 6.18.33; 6.19 to before 7.0.10 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.6 to before 6.12.91; 6.13 to before 6.18.33; 6.19 to before 7.0.10 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.1.191, 6.6.160, 6.12.91, 6.18.33, 7.0.10, 7.1
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
Not affected: 1 product
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2026-53129
- 2026-10-03 Alias added: GHSA-76p3-3v32-9xxh
- 2026-10-21 Fix available: Linux/[email protected], Linux/Linux@cbdd6f0fb19a0ce8a013acd80ac87a62f57fa20d · CNA
- 2026-10-21 1 new reference · CNA
- 2026-10-30 Fix available: Linux/Linux@40148c615687c1692712e50a6de53d62dfbfc20f, Linux/[email protected] · CNA
- 2026-10-30 1 new reference · CNA
- 2026-11-06 CISA SSVC decision points changed
References
Patch 4
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Sources
- CVE-2026-53129 · CVE Program
- CVE-2026-53129 · NVD
- FIRST EPSS
- GHSA-76p3-3v32-9xxh · GitHub Advisory Database · CC BY 4.0
- CVE-2026-53129 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences