Local kernel compromise via stale VFS path dereference
Published Apr 25, 2026 · Updated Apr 25, 2026
A race condition in Linux Kernel allows local users to access freed VFS path data through an exact UNIX socket diagnostic lookup. The sk_diag_dump_vfs function in net/unix/diag.c dereferences u->path without unix_state_lock while unix_release_sock can clear it and release the path reference. Local low-privileged access and winning the socket-release race are required; a successful stale dereference permits kernel compromise or a host crash.
Summary
What happened
A race condition in Linux Kernel allows local users to access freed VFS path data through an exact UNIX socket diagnostic lookup. The sk_diag_dump_vfs function in net/unix/diag.c dereferences u->path without unix_state_lock while unix_release_sock can clear it and release the path reference. Local low-privileged access and winning the socket-release race are required; a successful stale dereference permits kernel compromise or a host crash.
The record
- CVE
- CVE-2026-31673
- Published
- Apr 25, 2026
- Updated
- Apr 25, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 25, 2026CVE publishedPublication date reported by the CVE source.
- Apr 25, 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=3.3
- Affected versionversion=5f7b0569460b7d8d01ca776430a00505a68b7584 <0c739f3785f84af695952c2bac8be2f45082c9b8
- Affected versionversion=5f7b0569460b7d8d01ca776430a00505a68b7584 <39897df386376912d561d4946499379effa1e7ef
- Affected versionversion=5f7b0569460b7d8d01ca776430a00505a68b7584 <900a4e0910e98b8caef117d5df00471fa438dcf9
- Affected versionversion=5f7b0569460b7d8d01ca776430a00505a68b7584 <bdf206e740bf2919d818f132c8c9cc7ed91d11c0
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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