CVE-2025-21846

MEDIUM EPSS 11.3%
Published Mar 12, 20251y ago · Modified Jun 17, 20262w ago
5.5 CVSS 3.1
Medium
Find Similar
Published Mar 12, 2025 1y ago
Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: acct: perform last write from workqueue In [1] it was reported that the acct(2) system call can be used to trigger NULL deref in cases where it is set to write to a file that triggers an internal lookup. This can e.g., happen when pointing acc(2) to /sys/power/resume. At the point the where the write to this file happens the calling task has already exited and called exit_fs(). A lookup will thus trigger a NULL-deref when accessing current->fs. Reorganize the code so that the the final write happens from the workqueue but with the caller's credentials. This preserves the (strange) permission model and has almost no regression risk. This api should stop to exist though.

CVSS Details

Base Score
5.5
Exploitability
1.8
Impact
3.6
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

EPSS Exploit Probability
11.3% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-476 NULL Pointer Dereference Memory Safety

Affected Products 7

VendorProductVersionRange
linuxlinux_kernel*≥2.6.12  –  <6.1.130
linuxlinux_kernel*≥6.2  –  <6.6.80
linuxlinux_kernel*≥6.7  –  <6.12.17
linuxlinux_kernel*≥6.13  –  <6.13.5
linuxlinux_kernel6.14any
linuxlinux_kernel6.14any
linuxlinux_kernel6.14any

References 11

  • cert-portal.siemens.com https://cert-portal.siemens.com/productcert/html/ssa-265688.html
  • git.kernel.org https://git.kernel.org/stable/c/56d5f3eba3f5de0efdd556de4ef381e109b973a9
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5a59ced8ffc71973d42c82484a719c8f6ac8f7f7
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5c928e14a2ccd99462f2351ead627b58075bb736
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5d5b936cfa4b0d5670ca7420ef165a074bc008eb
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5ee8da9bea70dda492d61f075658939af33d8410
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8acbf4a88c6a98c8ed00afd1a7d1abcca9b4735e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a8136afca090412a36429cb6c2543c714d9c0f84
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b03782ae707cc45e65242c7cddd8e28f1c22cde5
    Patch
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/56d5f3eba3f5de0efdd556de4ef381e109b973a9
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5a59ced8ffc71973d42c82484a719c8f6ac8f7f7
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5c928e14a2ccd99462f2351ead627b58075bb736
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5d5b936cfa4b0d5670ca7420ef165a074bc008eb
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/5ee8da9bea70dda492d61f075658939af33d8410
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/8acbf4a88c6a98c8ed00afd1a7d1abcca9b4735e
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/a8136afca090412a36429cb6c2543c714d9c0f84
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/b03782ae707cc45e65242c7cddd8e28f1c22cde5
    Patch