CVE-2026-93117
kernel: usb: fix UAF when probe runs concurrent to dyn ID removal
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 17, 2026
Updated · October 21, 2026
Description
A flaw was found in the Linux kernel's USB subsystem. This use-after-free (UAF) vulnerability occurs when a dynamic ID is removed concurrently while the usb_probe_interface function is still using it. A local attacker could potentially exploit this timing issue, leading to memory corruption and potentially arbitrary code execution or a denial of service.
Statement
A use-after-free can occur in the USB driver core because usb_match_dynamic_id returned a pointer to a dynamic usb_device_id that is only protected while usb_dynids_lock is held. If remove_id_store removes the same dynamic ID through sysfs while usb_probe_interface is still using the returned pointer, the probe path may pass a stale usb_device_id to the driver callback. For the CVSS the PR:H value is used because reliable triggering requires write access to the USB driver dynamic ID sysfs interface, which is normally restricted to an administrator. The issue is not network reachable and requires a local control plane action plus a race with device probing. Impact is at least denial of service via kernel crash and in the paranoid case may include broader confidentiality or integrity impact because the bug class is kernel use-after-free.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 4.1CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
CWE-416 · Use After Free