CVE-2026-80947
kernel: wifi: rtl8xxxu: fix use-after-free from rx_urb_wq on stop
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 11, 2026
Updated · October 30, 2026
Description
A flaw was found in the Linux kernel's rtl8xxxu Wi-Fi driver. A race condition exists during the driver's stop process, specifically when handling receive (RX) Universal Serial Bus (USB) Request Blocks (URBs). This allows a worker to access memory that has already been freed, leading to a use-after-free vulnerability. This issue can result in system instability or a denial of service.
Statement
A use after free can occur in the rtl8xxxu WiFi driver because rx_urb_wq may remain queued or running while the device stop and disconnect path tears down RX URBs and later frees priv. Active RX traffic can arm the worker from the RX completion path, and a following stop or USB disconnect can let rtl8xxxu_rx_urb_work recover a stale priv pointer and dereference priv udev after ieee80211_free_hw. For the CVSS the PR:L is selected for the paranoid score because reliable triggering usually requires a local user context or delegated device control to cause the stop or disconnect condition, while nearby wireless traffic alone is not enough to complete the teardown race. The issue is not directly network reachable. Adjacent wireless traffic may help create RX pressure, but the security boundary crossing depends on a local teardown event. Impact is at least denial of service via kernel crash, and in worst case may allow broader confidentiality or integrity impact due to a real use after free race in kernel memory.
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 · 4.7CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-416 · Use After Free