# CVE-2026-80955

## Summary

- **CVE ID:** CVE-2026-80955
- **Severity:** HIGH
- **CVSS Score:** 7.8 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
- **CWE:** N/A
- **Published:** Sep 11, 2026
- **Last Modified:** Sep 13, 2026

## Description

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segment data is no longer valid.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.

## Affected Products

- Linux — Linux (1d57628ff95b32d5cfa8d8f50e07690c161e9cf0)
- Linux — Linux (6.18)
- Linux — Linux (0)
- Linux — Linux (6.18.50)
- Linux — Linux (7.2.4)
- Linux — Linux (7.3-rc1)

## References

- [CNA](https://git.kernel.org/stable/c/1894fc7a3bab90143dcd26ef8ee27040ef4a7501)
- [CNA](https://git.kernel.org/stable/c/f39a3e9cc5946473e16d6f5071b2ee0216c56d06)
- [CNA](https://git.kernel.org/stable/c/c2e894eac398b258f12fdec73ed6ba081047f7b3)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.16%
- **EPSS Percentile:** 5.3

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-18._