Bug 2460734 (CVE-2026-31473)

Summary: CVE-2026-31473 kernel: media: mc, v4l2: serialize REINIT and REQBUFS with req_queue_mutex
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's media, mc, and v4l2 subsystems. A race condition can occur when MEDIA_REQUEST_IOC_REINIT runs concurrently with VIDIOC_REQBUFS(0) queue teardown paths, leading to a use-after-free vulnerability. This flaw could allow a local attacker to cause a system crash (denial of service) or potentially execute arbitrary code with elevated privileges.
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Description OSIDB Bzimport 2026-04-22 15:08:09 UTC 
In the Linux kernel, the following vulnerability has been resolved:

media: mc, v4l2: serialize REINIT and REQBUFS with req_queue_mutex

MEDIA_REQUEST_IOC_REINIT can run concurrently with VIDIOC_REQBUFS(0)
queue teardown paths. This can race request object cleanup against vb2
queue cancellation and lead to use-after-free reports.

We already serialize request queueing against STREAMON/OFF with
req_queue_mutex. Extend that serialization to REQBUFS, and also take
the same mutex in media_request_ioctl_reinit() so REINIT is in the
same exclusion domain.

This keeps request cleanup and queue cancellation from running in
parallel for request-capable devices.
Comment 1 Keith Grant 2026-04-22 18:19:20 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026042255-CVE-2026-31473-fad0@gregkh/T