CVE-2026-31673: Linux kernel · af_unix: read UNIX_DIAG_VFS data under unix_state_lock
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 7.8 High · fixed in e7339db13b9ddb63417b12da55fd6191e59f7442 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:18 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in e7339db13b9ddb63417b12da55fd6191e59f7442, c3ec44ab4526bbc4b6c9fc845af86488244f4c9b, bdf206e740bf2919d818f132c8c9cc7ed91d11c0 +5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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AI-suggested
A fix is available and has been applied in multiple Linux kernel commits as listed in the establishedFacts.fixedVersions. Users and administrators should update to a Linux kernel version that includes these fixes to mitigate this vulnerability.
Description
CVE-2026-31673 is a high-severity vulnerability in the Linux kernel affecting version 3.3. It involves improper handling of UNIX_DIAG_VFS data under the unix_state_lock, where inode and device numbers were read without holding the lock, potentially causing data instability. The issue has been resolved by ensuring the VFS data is read while holding the unix_state_lock and emitting the netlink attribute after releasing the lock to maintain data stability during reply construction.
References
- git.kernel.org/stable/c/e7339db13b9ddb63417b12da55fd6191e59f7442 (opens in a new tab)
- git.kernel.org/stable/c/4f6a8f10182c3a9d22e8eb183957ae7ade9e4bf7 (opens in a new tab)
- git.kernel.org/stable/c/c3ec44ab4526bbc4b6c9fc845af86488244f4c9b (opens in a new tab)
- git.kernel.org/stable/c/b9232421a77a649c9376c99fdfc8cb7f79cad34c (opens in a new tab)
- git.kernel.org/stable/c/0c739f3785f84af695952c2bac8be2f45082c9b8 (opens in a new tab)
- git.kernel.org/stable/c/900a4e0910e98b8caef117d5df00471fa438dcf9 (opens in a new tab)
- git.kernel.org/stable/c/bdf206e740bf2919d818f132c8c9cc7ed91d11c0 (opens in a new tab)
- git.kernel.org/stable/c/39897df386376912d561d4946499379effa1e7ef (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-784472.html (opens in a new tab)