CVE-2025-21796 — Use After Free in Linux
Severity
7.8HIGHNVD
OSV8.8OSV7.1OSV5.5
EPSS
0.0%
top 97.96%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
Timeline
PublishedFeb 27
Latest updateNov 19
Description
In the Linux kernel, the following vulnerability has been resolved:
nfsd: clear acl_access/acl_default after releasing them
If getting acl_default fails, acl_access and acl_default will be released
simultaneously. However, acl_access will still retain a pointer pointing
to the released posix_acl, which will trigger a WARNING in
nfs3svc_release_getacl like this:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 26 PID: 3199 at lib/refcount.c:28
refcount_…
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitability: 1.8 | Impact: 5.9