---
id: CVE-2025-37808
title: 'crypto: null - Use spin lock instead of mutex'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  crypto: null - Use spin lock instead of mutex

  As the null algorithm may be freed in softirq context through
  af_alg, use spin locks instead of mutexes to protect the de…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 <
    f7a5a5c8e1ec16a4b2041398abe95de0e14572ef
  - >-
    Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 <
    e307c54ac8198bf09652c72603ba6e6d97798410
  - >-
    Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 <
    1dd4a8561d85dea545cf93f56efc48df8176e218
  - >-
    Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 <
    e27244cbe10658a66b8775be7f0acc4ad2f618d6
  - >-
    Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 <
    1b66a5920b7fc7cc6251192a3fcad115b6d75dd5
  - >-
    Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 <
    0486de3c1b8223138dcc614846bd76364f758de6
  - >-
    Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 <
    8cf2945512a8c0ef74ddd5b5a4f6b6a2fb1a4efb
  - >-
    Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 <
    dcc47a028c24e793ce6d6efebfef1a1e92f80297
  - Linux 4.2
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-11-05T20:41:07.414539Z'
published: '2025-05-08'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T20:41:54.753Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-37808'
references:
  - url: 'https://git.kernel.org/stable/c/f7a5a5c8e1ec16a4b2041398abe95de0e14572ef'
  - url: 'https://git.kernel.org/stable/c/e307c54ac8198bf09652c72603ba6e6d97798410'
  - url: 'https://git.kernel.org/stable/c/1dd4a8561d85dea545cf93f56efc48df8176e218'
  - url: 'https://git.kernel.org/stable/c/e27244cbe10658a66b8775be7f0acc4ad2f618d6'
  - url: 'https://git.kernel.org/stable/c/1b66a5920b7fc7cc6251192a3fcad115b6d75dd5'
  - url: 'https://git.kernel.org/stable/c/0486de3c1b8223138dcc614846bd76364f758de6'
  - url: 'https://git.kernel.org/stable/c/8cf2945512a8c0ef74ddd5b5a4f6b6a2fb1a4efb'
  - url: 'https://git.kernel.org/stable/c/dcc47a028c24e793ce6d6efebfef1a1e92f80297'
tags:
  - cve.org
epss: 0.00214
epssPercentile: 0.11806
ingestedAt: '2026-11-05T22:38:31.872Z'
---

## Overview

In the Linux kernel, the following vulnerability has been resolved:

crypto: null - Use spin lock instead of mutex

As the null algorithm may be freed in softirq context through
af_alg, use spin locks instead of mutexes to protect the default
null algorithm.

## Affected

- `Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 < f7a5a5c8e1ec16a4b2041398abe95de0e14572ef`
- `Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 < e307c54ac8198bf09652c72603ba6e6d97798410`
- `Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 < 1dd4a8561d85dea545cf93f56efc48df8176e218`
- `Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 < e27244cbe10658a66b8775be7f0acc4ad2f618d6`
- `Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 < 1b66a5920b7fc7cc6251192a3fcad115b6d75dd5`
- `Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 < 0486de3c1b8223138dcc614846bd76364f758de6`
- `Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 < 8cf2945512a8c0ef74ddd5b5a4f6b6a2fb1a4efb`
- `Linux >= 330234638e16b7b95e8e5e6be719a61a93f074b8 < dcc47a028c24e793ce6d6efebfef1a1e92f80297`
- `Linux 4.2`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.