CVE-2026-31504: Linux kernel · Race Condition
Affects Linux kernelSource CVE Database V5
Mentioned vulnerabilities
Not known to be exploited · CVSS 7.8 High · fixed in ee642b1962caa9aa231c01abbd58bc453ae6b66e : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:01 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% 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 ee642b1962caa9aa231c01abbd58bc453ae6b66e, d0c7cdc15fdf8c4f91aca1928e52295d175b6ec6, ceccbfc6de720ad633519a226715989cfb065af1 +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 22 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
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in
|
AI-suggested
A fix is available and has been applied in the Linux kernel as indicated by multiple fixed commit versions. Users and administrators should update to a patched kernel version containing these fixes to remediate the vulnerability. No additional mitigation steps are indicated beyond applying the official patch.
Description
CVE-2026-31504 is a use-after-free vulnerability in the Linux kernel's network subsystem related to the fanout socket handling in packet_release(). A race condition involving NETDEV_UP events can cause a socket to be re-registered improperly, leaving dangling pointers and inconsistent state in the fanout array. This flaw was fixed by ensuring proper zeroing of internal counters during socket release to prevent re-registration races.
References
- git.kernel.org/stable/c/ee642b1962caa9aa231c01abbd58bc453ae6b66e (opens in a new tab)
- git.kernel.org/stable/c/42cfd7898eeed290c9fb73f732af1f7d6b0a703e (opens in a new tab)
- git.kernel.org/stable/c/1b4c03f8892d955385c202009af7485364731bb9 (opens in a new tab)
- git.kernel.org/stable/c/654386baef228c2992dbf604c819e4c7c35fc71b (opens in a new tab)
- git.kernel.org/stable/c/75fe6db23705a1d55160081f7b37db9665b1880b (opens in a new tab)
- git.kernel.org/stable/c/d0c7cdc15fdf8c4f91aca1928e52295d175b6ec6 (opens in a new tab)
- git.kernel.org/stable/c/ceccbfc6de720ad633519a226715989cfb065af1 (opens in a new tab)
- git.kernel.org/stable/c/42156f93d123436f2a27c468f18c966b7e5db796 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-082556.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-019113.html (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-457936.html (opens in a new tab)