UBUNTU-CVE-2025-21893

Advisory lineage Upstream: 1 Downstream: 4
Published: 31 Mar 2025, 20:15
Last modified:04 Feb 2026, 04:15

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
3.1 (osv_ubuntu)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

31 Mar 2025, 20:15
Published
Vulnerability first disclosed
04 Feb 2026, 04:15
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: keys: Fix UAF in key_put() Once a key's reference count has been reduced to 0, the garbage collector thread may destroy it at any time and so key_put() is not allowed to touch the key after that point. The most key_put() is normally allowed to do is to touch key_gc_work as that's a static global variable. However, in an effort to speed up the reclamation of quota, this is now done in key_put() once the key's usage is reduced to 0 - but now the code is looking at the key after the deadline, which is forbidden. Fix this by using a flag to indicate that a key can be gc'd now rather than looking at the key's refcount in the garbage collector.

CVSS Metrics

  • v3.1HIGHScore: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • ubuntulinux-allwinner-5.19

    all

  • ubuntulinux-aws-5.0

    all

  • ubuntulinux-aws-5.11

    all

  • ubuntulinux-aws-5.13

    all

  • ubuntulinux-aws-5.19

    all

  • ubuntulinux-aws-5.3

    all

  • ubuntulinux-aws-5.8

    all

  • ubuntulinux-aws-6.2

    all

  • ubuntulinux-aws-6.5

    all

  • ubuntulinux-azure

    all

  • ubuntulinux-azure-5.11

    all

  • ubuntulinux-azure-5.13

    all

  • ubuntulinux-azure-5.19

    all

  • ubuntulinux-azure-5.3

    all

  • ubuntulinux-azure-5.8

    all

  • ubuntulinux-azure-6.11

    < 6.11.0-1018.18~24.04.1

  • ubuntulinux-azure-6.2

    all

  • ubuntulinux-azure-6.5

    all

  • ubuntulinux-azure-edge

    all

  • ubuntulinux-azure-fde

    all

  • ubuntulinux-azure-fde-5.19

    all

  • ubuntulinux-azure-fde-6.2

    all

  • ubuntulinux-gcp

    all

  • ubuntulinux-gcp-5.11

    all

  • ubuntulinux-gcp-5.13

    all

  • ubuntulinux-gcp-5.19

    all

  • ubuntulinux-gcp-5.3

    all

  • ubuntulinux-gcp-5.8

    all

  • ubuntulinux-gcp-6.11

    < 6.11.0-1016.16~24.04.1

  • ubuntulinux-gcp-6.2

    all

  • ubuntulinux-gcp-6.5

    all

  • ubuntulinux-gke

    all

  • ubuntulinux-gke-4.15

    all

  • ubuntulinux-gke-5.15

    all

  • ubuntulinux-gke-5.4

    all

  • ubuntulinux-gkeop

    all

  • ubuntulinux-gkeop-5.15

    all

  • ubuntulinux-gkeop-5.4

    all

  • ubuntulinux-hwe

    all

  • ubuntulinux-hwe-5.11

    all

  • ubuntulinux-hwe-5.13

    all

  • ubuntulinux-hwe-5.19

    all

  • ubuntulinux-hwe-5.8

    all

  • ubuntulinux-hwe-6.11

    < 6.11.0-28.28~24.04.1

  • ubuntulinux-hwe-6.2

    all

  • ubuntulinux-hwe-6.5

    all

  • ubuntulinux-hwe-edge

    all | all

  • ubuntulinux-intel-5.13

    all

  • ubuntulinux-intel-iot-realtime

    all

  • ubuntulinux-lowlatency-hwe-5.19

    all

Showing first 50 affected entries in server-rendered view.

References (10)