Race condition in Linux kernel - CVE-2026-63874

 

Race condition in Linux kernel - CVE-2026-63874

Published: July 20, 2026


Vulnerability identifier: #VU138783
CSH Severity: Low
CVSS v4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-63874
CWE-ID: CWE-362
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a race condition in the mctp-usb driver when stopping the network device while rx retry work and urb completion are handled concurrently. A local user can trigger concurrent stop and retry activity to cause a denial of service.

The issue can leave a receive urb queued and its completion can reschedule retry work after device shutdown.


Affected software

Linux kernel

How to mitigate CVE-2026-63874

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3

External References

Related Security Bulletins