CVE-2026-80955

In the Linux kernel, the following vulnerability has been resolved: dm-pcache: fix use-after-free and invalid seg operations in kset_replay() In kset_replay, when key->seg_gen is stale (key->seg_gen < key->cache_pos.cache_seg->gen), cache_key_put(key) is called but then key->cache_pos.cache_seg is accessed as the argument to cache_seg_get(). This is a use-after-free on the freed key memory. Although mempool recycled memory is not immediately reclaimed or overwritten in practice, this is still a potential UAF bug. Additionally, for expired invalid keys, setting the cache->seg_map bit and calling cache_seg_get() is unreasonable since the corresponding segment data is no longer valid. Fix both issues by moving cache_seg_get() and __set_bit() after the gen check, so they only execute for valid keys, and using continue to skip invalid keys.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/1894fc7a3bab90143dcd26ef8ee27040ef4a7501
https://git.kernel.org/stable/c/c2e894eac398b258f12fdec73ed6ba081047f7b3
https://git.kernel.org/stable/c/f39a3e9cc5946473e16d6f5071b2ee0216c56d06

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 20:19

Updated : 2026-09-13 07:17

NVD link : CVE-2026-80955

Mitre link : CVE-2026-80955

CVE.ORG link : CVE-2026-80955

JSON object : View

Products Affected

No product.

CWE

No CWE.

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