Out-of-bounds write in Linux kernel dm-pcache key handling
Key facts
- Attack vector
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- Privileges required
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- User interaction
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- Attack complexity
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- Impact type
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- Confidentiality · integrity · availability
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- Fix status
- Fixed
No CVSS vector from any source. Fix status from CNA.
Summary
The dm-pcache target in the Linux kernel, from 6.18, uses a logical key offset read from the cache device without checking it against the device size. An offset past the device lets rb_insert() write through a subtree pointer outside the req_key_tree subtrees array during replay, which corrupts kernel memory.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Description from the CNA
In the Linux kernel, the following vulnerability has been resolved: dm-pcache: bound the logical key offset from persistent memory cache_key_decode() takes a key's logical off from the cache device and later indexes req_key_tree->subtrees[] by it in get_subtree(). An off past the device forms a subtree pointer outside the array, which rb_insert() writes through during replay. Reject a key of zero length, or whose off+len (computed in 64 bits) exceeds the device size, before it is used.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
Update the Linux kernel to 6.18.52, 7.2.10 or 7.3, which contain the fix.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
- Fix · CNA Linux (Linux) Fixed in 6.18.52, 7.2.10, 7.3
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
Not affected: 7 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4
- Red Hat OpenShift Container Platform 5
Timeline
- 2026-10-18 Threatist record created from CVE-2026-98867
- 2026-10-18 Alias added: GHSA-f472-jf6w-c35h
- 2026-10-19 Fix available: Linux/[email protected] · CNA
- 2026-10-24 Affected versions changed · Red Hat
- 2026-10-24 CVSS score added · Red Hat
- 2026-11-06 Affected versions changed · Red Hat
References
More Linux vulnerabilities
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- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2021-02452 Incorrect authorization in Ubuntu linux kernel 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
Sources
- CVE-2026-98867 · CVE Program
- CVE-2026-98867 · NVD
- FIRST EPSS
- GHSA-f472-jf6w-c35h · GitHub Advisory Database · CC BY 4.0
- CVE-2026-98867 · Red Hat security data · CC BY 4.0
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