CVE-2026-31408
HighIn the Linux kernel, the following vulnerability has been resolved: Bluetooth: SCO: Fix use-after-free in sco_recv_frame() due to missing sock_hold sco_recv_frame() reads conn->sk under sco_conn_lock() but immediately releases the lock without holding a reference to the socket. A concurrent close() can free the socket between the lock release and the subsequent sk->sk_state access, resulting in a use-after-free. Other functions in the same file (sco_sock_timeout(), sco_conn_del()) correctly use sco_sock_hold() to safely hold a reference under the lock. Fix by using sco_sock_hold() to take a reference before releasing the lock, and adding sock_put() on all exit paths.
CVSS 3.1 score
8.8
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness type
CWE-416CVE-2026-31408 is a Use After Free vulnerability
What is Use After Free?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE
Affected versions
Linux kernel versions
2.6.12
and later are affected. Fixed in
5.15.203,
6.1.168,
6.6.131,
6.12.80,
6.18.21,
6.19.11,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-31408 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
-
PatchKernel patch commithttps://git.kernel.org/stable/c/108b81514d8f2535eb16651495cefb2250528db3
-
PatchKernel patch commithttps://git.kernel.org/stable/c/45aaca995e4a7a05b272a58e7ab2fff4f611b8f1
-
PatchKernel patch commithttps://git.kernel.org/stable/c/598dbba9919c5e36c54fe1709b557d64120cb94b
Frequently asked questions
-
What is CVE-2026-31408?
CVE-2026-31408 is a High severity Linux kernel vulnerability with a CVSS score of 8.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 2.6.12 onward and has been patched in 5.15.203, 6.1.168, 6.6.131 and others. CVE-2026-31408 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
-
What is the CVSS score for CVE-2026-31408?
CVE-2026-31408 has a CVSS score of 8.8 out of 10, rated High severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. -
Is there a patch available for CVE-2026-31408?
Yes — CVE-2026-31408 has been patched. Fixed versions include 5.15.203, 6.1.168, 6.6.131 and others. If you are running Linux kernel 2.6.12 or later up to the fix versions, apply the relevant patch for your kernel branch.
-
Is CVE-2026-31408 actively exploited?
No — CVE-2026-31408 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
-
What is Use After Free (CWE-416)?
The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. View CWE-416 on MITRE CWE →