CVE-2024-26875 Linux CVE debrief

Who should care

Linux kernel maintainers, distro security teams, and operators of systems that may load the pvrusb2 media driver should care. Because the CVSS vector is local and requires high privileges, the main concern is untrusted local access on systems running affected kernel versions.

Technical summary

The issue is a race in drivers/media/usb/pvrusb2/pvrusb2-context.c. According to the supplied analysis, setting disconnect_flag too early allowed a second task to satisfy its condition and release mp while the first task still expected it to remain valid, leading to a use-after-free in pvr2_context_set_notify(). The documented resolution is to move the disconnect_flag assignment after the remaining disconnect logic in pvr2_context_disconnect(), which closes the race window. NVD maps the flaw to CWE-416 and lists affected Linux kernel version ranges up through 6.8.2, with stable backports provided via kernel.org references.

Defensive priority

Medium priority for patching. The flaw is serious because it can impact kernel integrity and availability, but the attack surface is limited to local, high-privilege conditions per the CVSS vector.

Recommended defensive actions

• Apply the relevant Linux kernel stable update that includes the pvrusb2 disconnect-handling fix.
• Verify whether your kernels fall within the affected ranges listed by NVD and plan upgrades accordingly.
• If the pvrusb2 driver is not needed, reduce exposure by avoiding unnecessary module loading on affected systems.
• Follow your distribution or vendor advisories for backported fixes and confirm the patched kernel build is deployed across all affected hosts.

Evidence notes

The supplied source describes a KASAN-reported slab-use-after-free in pvr2_context_set_notify() and explicitly states that moving the disconnect_flag assignment to after the rest of pvr2_context_disconnect() avoids the issue. NVD lists the issue as CVSS 3.1 AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H and provides affected Linux kernel version ranges ending at 4.19.311, 5.4.273, 5.10.214, 5.15.153, 6.1.83, 6.6.23, 6.7.11, and 6.8.2.

Official resources