The mbcache feature in the ext2 and ext4 filesystem implementations in the Linux kernel…
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Will not fix Red Hat: no fix planned
Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat.
Summary
The mbcache feature in the ext2 and ext4 filesystem implementations in the Linux kernel before 4.6 mishandles xattr block caching, which allows local users to cause a denial of service (soft lockup) via filesystem operations in environments that use many attributes, as demonstrated by Ceph and Samba.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 5 | Affected | No fix planned: Will not fix |
Not affected: 3 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise MRG 2
Timeline
- 2026-10-02 Threatist record created from CVE-2015-8952
- 2026-10-03 Alias added: GHSA-r248-wpg2-5hw4
References
Patch 5
- [oss-security] 20160825 Re: CVE request: Linux kernel mbcache lock contention denial of service.
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=82939d7999dfc1f1998c4b1c12e2f19edbdff272
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=be0726d33cb8f411945884664924bed3cb8c70ee
- https://github.com/torvalds/linux/commit/be0726d33cb8f411945884664924bed3cb8c70ee
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f9a61eb4e2471c56a63cd804c7474128138c38ac
Advisory 7
- https://bugzilla.redhat.com/show_bug.cgi?id=1360968
- https://github.com/torvalds/linux/commit/82939d7999dfc1f1998c4b1c12e2f19edbdff272
- USN-3582-1
- https://bugzilla.kernel.org/show_bug.cgi?id=107301
- [oss-security] 20160822 CVE request: Linux kernel mbcache lock contention denial of service.
- https://lwn.net/Articles/668718/
- USN-3582-2
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2015-8952 · CVE Program
- CVE-2015-8952 · NVD
- FIRST EPSS
- GHSA-r248-wpg2-5hw4 · GitHub Advisory Database · CC BY 4.0
- CVE-2015-8952 · 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