CVE-2026-31408: Linux kernel · Use After Free
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 8.8 High · fixed in e76e8f0581ef555eacc11dbb095e602fb30a5361 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:18 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 23% 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 e76e8f0581ef555eacc11dbb095e602fb30a5361, d57384e27d1ebf0047e3f00a6e1181b8be9857a2, b0a7da0e3f7442545f071499beb36374714bb9de +5
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 6 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 in the Linux kernel as indicated by multiple fixed commit versions. Users and administrators should update to a Linux kernel version that includes these fixes. Since this is not a cloud service, manual patching is required. There are no indications of known exploits in the wild at this time.
Description
CVE-2026-31408 is a use-after-free vulnerability in the Linux kernel's Bluetooth SCO implementation. The flaw occurs in the sco_recv_frame() function, which accesses a socket pointer without properly holding a reference, allowing a concurrent close operation to free the socket prematurely. This can lead to use-after-free conditions. The issue is fixed by adding proper reference counting with sco_sock_hold() and sock_put().
References
- git.kernel.org/stable/c/37e18bc8c9a70d77bd099e2273f328b3bc7f6d0d (opens in a new tab)
- git.kernel.org/stable/c/d57384e27d1ebf0047e3f00a6e1181b8be9857a2 (opens in a new tab)
- git.kernel.org/stable/c/b0a7da0e3f7442545f071499beb36374714bb9de (opens in a new tab)
- git.kernel.org/stable/c/45aaca995e4a7a05b272a58e7ab2fff4f611b8f1 (opens in a new tab)
- git.kernel.org/stable/c/108b81514d8f2535eb16651495cefb2250528db3 (opens in a new tab)
- git.kernel.org/stable/c/7197462e90b8ce15caa1ae15d4bc2bb8cd21b11e (opens in a new tab)
- git.kernel.org/stable/c/e76e8f0581ef555eacc11dbb095e602fb30a5361 (opens in a new tab)
- git.kernel.org/stable/c/598dbba9919c5e36c54fe1709b557d64120cb94b (opens in a new tab)