Kernel resource leak via unsynchronized nfsd shutdown
Published Sep 11, 2026 · Updated Sep 11, 2026
Race condition in Linux 6.9 allows attackers to leak nfsd file objects and associated state during per-network shutdown. The shrinker, garbage-collection worker, and fsnotify or lease callbacks can unhash an nfsd_file before queuing it for delayed disposal, while nfsd_file_cache_shutdown_net can finish draining the per-network list first. The race requires concurrent NFSD file-cache disposal and per-network shutdown; the documented consequence is a persistent leak of the file and its associated state.
Summary
What happened
Race condition in Linux 6.9 allows attackers to leak nfsd file objects and associated state during per-network shutdown. The shrinker, garbage-collection worker, and fsnotify or lease callbacks can unhash an nfsd_file before queuing it for delayed disposal, while nfsd_file_cache_shutdown_net can finish draining the per-network list first. The race requires concurrent NFSD file-cache disposal and per-network shutdown; the documented consequence is a persistent leak of the file and its associated state.
The record
- CVE
- CVE-2026-89667
- Published
- Sep 11, 2026
- Updated
- Sep 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 11, 2026CVE publishedPublication date reported by the CVE source.
- Sep 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=6.9
- Affected versionversion=ffb402596147ac583f3464ff5c48feb9423e3838 <08af9593e2b472fd98c00faf1bf03bdbb7203477
- Affected versionversion=ffb402596147ac583f3464ff5c48feb9423e3838 <40162cfea79b9510380decfdd1795b754dc9f972
- Affected versionversion=ffb402596147ac583f3464ff5c48feb9423e3838 <6d6b9f6a75c3767250e9c23ace4e384ab8f7843e
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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