CVE-2025-21893 (GCVE-0-2025-21893)
Vulnerability from cvelistv5
Published
2025-03-31 19:41
Modified
2026-05-11 21:08
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: 9578e327b2b4935a25d49e3891b8fcca9b6c10c6
Version: 9578e327b2b4935a25d49e3891b8fcca9b6c10c6
Version: 9578e327b2b4935a25d49e3891b8fcca9b6c10c6
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