Freed-memory read via unpinned NFSD client
Published Sep 16, 2026 · Updated Sep 16, 2026
Use-after-free in Linux NFSD 3.17 and later allows attackers to trigger a freed-memory read during concurrent NFS client teardown. The nfs4_laundromat path drops nn->client_lock before nfs4_put_stid() dereferences an unpinned nfs4_client, while force_expire_client() or __destroy_client() can free that client. Reachability requires a timed-out close_lru entry to be reaped during concurrent client teardown; no further security impact has been published.
Summary
What happened
Use-after-free in Linux NFSD 3.17 and later allows attackers to trigger a freed-memory read during concurrent NFS client teardown. The nfs4_laundromat path drops nn->client_lock before nfs4_put_stid() dereferences an unpinned nfs4_client, while force_expire_client() or __destroy_client() can free that client. Reachability requires a timed-out close_lru entry to be reaped during concurrent client teardown; no further security impact has been published.
The record
- CVE
- CVE-2026-90037
- Published
- Sep 16, 2026
- Updated
- Sep 16, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Sep 16, 2026CVE publishedPublication date reported by the CVE source.
- Sep 16, 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=217526e7ecc9f6f243e976772e81eab7ab986a4c <2330b788d732f43668b965b3105b37ceb276dfea
- Affected versionversion=217526e7ecc9f6f243e976772e81eab7ab986a4c <83dd59ac1c3455c2c7d8ddb582d980a13199b9b3
- Affected versionversion=217526e7ecc9f6f243e976772e81eab7ab986a4c <e57a9ed34ea8c17e831de59b8f1a6b2d80d347a1
- Affected versionversion=3.17
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
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Public exploit references
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Technologies
Your stack
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Your stack
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