---
id: CVE-2026-80956
title: 'kernel: dm-pcache: only hand out initialized cache segments (CVE-2026-80956)'
summary: >-
  A flaw was found in the Linux kernel's `dm-pcache` component. A crafted image
  can cause the `get_cache_segment()` function to return an uninitialized cache
  segment. This uninitialized segment, containing a null data pointer, is then
  used b…
severity: medium
cvss: 5.5
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'
cvssSource: vendor
cwe: CWE-824
vendor: Red Hat
product: Linux
affected:
  - >-
    Linux >= 1d57628ff95b32d5cfa8d8f50e07690c161e9cf0 <
    83e3116283ed2c6a6a1fa662862a4b4d7d2701a2
  - >-
    Linux >= 1d57628ff95b32d5cfa8d8f50e07690c161e9cf0 <
    692037ae1a7cfacc2f0c22c6e034c1dfee0e553f
  - >-
    Linux >= 1d57628ff95b32d5cfa8d8f50e07690c161e9cf0 <
    2df0fc042e299bae3c0f60ea5cd2af9285658e9f
  - Linux 6.18
published: '2026-09-11'
updated: '2026-09-14'
sourceUpdated: '2026-09-14T17:36:15+00:00'
source: CSAF
sourceUrl: 'https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80956.json'
references:
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80956.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-80956'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2532400'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-80956'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-80956'
  - url: >-
      https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-80956.mbox
  - url: 'https://git.kernel.org/stable/c/83e3116283ed2c6a6a1fa662862a4b4d7d2701a2'
  - url: 'https://git.kernel.org/stable/c/692037ae1a7cfacc2f0c22c6e034c1dfee0e553f'
  - url: 'https://git.kernel.org/stable/c/2df0fc042e299bae3c0f60ea5cd2af9285658e9f'
tags:
  - csaf
  - vex
  - red-hat
  - cve.org
epss: 0.00206
epssPercentile: 0.09454
ingestedAt: '2026-09-14T00:35:28.532Z'
---

## Overview

A flaw was found in the Linux kernel's `dm-pcache` component. A crafted image can cause the `get_cache_segment()` function to return an uninitialized cache segment. This uninitialized segment, containing a null data pointer, is then used by `cache_kset_close()` without a proper null check. This can lead to a system crash, resulting in a Denial of Service (DoS).

## Vendor advisories

- **Red Hat VEX** · Moderate · updated 2026-09-14 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-80956.json)

**kernel: dm-pcache: only hand out initialized cache segments** — rated Moderate by Red Hat. Released 2026-09-11, updated 2026-09-14.

Not affected:

- 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

## Remediation

Refer to the advisory for fix availability.