Kernel resource leak via premature AFS mmap refcount
Published May 27, 2026 · Updated May 27, 2026
Refcount leak in the AFS filesystem in Linux Kernel 6.17 allows local users to retain kernel resources through file mappings. afs_file_mmap_prepare calls afs_add_open_mmap before the memory manager decides whether to merge or allocate the VMA, so either outcome can strand the incremented vnode reference. Triggering requires local low-privileged access and an AFS file mapping; kernel.org does not disclose a concrete consequence beyond the leaked reference.
Summary
What happened
Refcount leak in the AFS filesystem in Linux Kernel 6.17 allows local users to retain kernel resources through file mappings. afs_file_mmap_prepare calls afs_add_open_mmap before the memory manager decides whether to merge or allocate the VMA, so either outcome can strand the incremented vnode reference. Triggering requires local low-privileged access and an AFS file mapping; kernel.org does not disclose a concrete consequence beyond the leaked reference.
The record
- CVE
- CVE-2026-46100
- Published
- May 27, 2026
- Updated
- May 27, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 27, 2026CVE publishedPublication date reported by the CVE source.
- May 27, 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=6.17
- Affected versionversion=9d5403b1036cdcd4be0f9f5568612c0e60e73d79 <48c7a0eaeea41da17d1d84d2d7a4c40be122b246
- Affected versionversion=9d5403b1036cdcd4be0f9f5568612c0e60e73d79 <f51f85c044809fbd39ac8ae07ac99bc43ce32bd5
- Affected versionversion=9d5403b1036cdcd4be0f9f5568612c0e60e73d79 <fbfc6578eaca12daa0c09df1e9ba7f2c657b49da
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Public exploit references
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Technologies
Your stack
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Your stack
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