Service interruption via unreleased AFS inode lock
Published Jan 31, 2025 · Updated May 11, 2026
Improper locking in Linux kernel AFS 6.8 through 6.12.10 allows local users to hold an inode lock via a preference write. afs_proc_addr_prefs_write returns directly when afs_split_string produces a negative argc, bypassing cleanup that releases the inode lock. Exploitation requires low-privileged local access to the AFS proc preference interface; the held lock can block later AFS operations, and pre-6.13 release candidates are also affected.
Summary
What happened
Improper locking in Linux kernel AFS 6.8 through 6.12.10 allows local users to hold an inode lock via a preference write. afs_proc_addr_prefs_write returns directly when afs_split_string produces a negative argc, bypassing cleanup that releases the inode lock. Exploitation requires low-privileged local access to the AFS proc preference interface; the held lock can block later AFS operations, and pre-6.13 release candidates are also affected.
The record
- CVE
- CVE-2025-21672
- Published
- Jan 31, 2025
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-667, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jan 31, 2025CVE publishedPublication date reported by the CVE source.
- May 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=6.8
- Affected versionversion=f94f70d39cc2d54079ebae934862198516315db2 <17a4fde81d3a7478d97d15304a6d61094a10c2e3
- Affected versionversion=f94f70d39cc2d54079ebae934862198516315db2 <22be1d90a6211c88dd093b25d1f3aa974d0d9f9d
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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