NFS server shutdown hang via reference leak
Published Aug 19, 2025 · Updated May 23, 2026
Race condition in Linux kernel 6.15.3 through 6.15.9 and 6.16 allows local users to hang NFS server shutdown via concurrent file opens. In nfsd_open_local_fh(), racing successful nfsd_file_acquire_local() calls each take a network-namespace reference, but the xchg() loser drops only its file reference and omits nfsd_net_put(). Two successful local-file acquisition calls must coincide; the leaked reference leaves nfsd_shutdown_net() waiting indefinitely when the server shuts down.
Summary
What happened
Race condition in Linux kernel 6.15.3 through 6.15.9 and 6.16 allows local users to hang NFS server shutdown via concurrent file opens. In nfsd_open_local_fh(), racing successful nfsd_file_acquire_local() calls each take a network-namespace reference, but the xchg() loser drops only its file reference and omits nfsd_net_put(). Two successful local-file acquisition calls must coincide; the leaked reference leaves nfsd_shutdown_net() waiting indefinitely when the server shuts down.
The record
- CVE
- CVE-2025-38567
- Published
- Aug 19, 2025
- Updated
- May 23, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-362, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 19, 2025CVE publishedPublication date reported by the CVE source.
- May 23, 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=6.15.3 <6.15.10
- Affected versionversion=6.16
- Affected versionversion=986a21ace186433e0397a59491646edad8c8d636 <fcb0a417fddb605530c4837e0996620f8ed38023
- Affected versionversion=e6f7e1487ab528a6c653bd0d42812ff2942846cd <c4bf8f26c51e51bbb840935659a7b3b65a802c07
- Affected versionversion=e6f7e1487ab528a6c653bd0d42812ff2942846cd <e5a73150776f18547ee685c9f6bfafe549714899
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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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