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.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Mon, 16 Jun 2025 19:00:00 +0000

Type Values Removed Values Added
First Time appeared Redhat
Redhat enterprise Linux
CPEs cpe:/o:redhat:enterprise_linux:10.0
Vendors & Products Redhat
Redhat enterprise Linux

Fri, 11 Apr 2025 03:00:00 +0000

Type Values Removed Values Added
Metrics threat_severity

Low

threat_severity

Moderate


Tue, 08 Apr 2025 16:15:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel

Wed, 02 Apr 2025 02:15:00 +0000


Mon, 31 Mar 2025 21:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416
Metrics cvssV3_1

{'score': 7.8, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Mon, 31 Mar 2025 20:00:00 +0000

Type Values Removed Values Added
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.
Title keys: Fix UAF in key_put()
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-05-04T07:23:40.081Z

Reserved: 2024-12-29T08:45:45.783Z

Link: CVE-2025-21893

cve-icon Vulnrichment

Updated: 2025-03-31T20:45:41.300Z

cve-icon NVD

Status : Analyzed

Published: 2025-03-31T20:15:14.613

Modified: 2025-04-08T15:48:59.010

Link: CVE-2025-21893

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-03-31T00:00:00Z

Links: CVE-2025-21893 - Bugzilla

cve-icon OpenCVE Enrichment

No data.