{"cve":"CVE-2026-80947","nvd":{"published":"2026-09-11T20:19:00.303","modified":"2026-10-21T13:20:01.770","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: rtl8xxxu: fix use-after-free from rx_urb_wq on stop\n\nrtl8xxxu arms rx_urb_wq from the RX completion path:\nrtl8xxxu_rx_complete() hands the URB to rtl8xxxu_queue_rx_urb(), which\nqueues it on rx_urb_pending_list and, once the list grows past\nRTL8XXXU_RX_URB_PENDING_WATER, schedules rx_urb_wq.  The worker\nrtl8xxxu_rx_urb_work() drains rx_urb_pending_list, recovers priv through\ncontainer_of, and resubmits each URB through rtl8xxxu_submit_rx_urb(),\nwhich anchors it on rx_anchor and dereferences priv->udev.\n\nrtl8xxxu_stop() cancels the sibling work items (c2hcmd_work, ra_watchdog,\nupdate_beacon_work) but never cancels rx_urb_wq, so a worker armed during\nthe last burst of RX traffic can run rtl8xxxu_rx_urb_work() after\nrtl8xxxu_disconnect() has called ieee80211_free_hw(), which frees priv,\nproducing a use-after-free.  The window opens under active RX traffic\n(pending count above the watermark) followed by a disconnect.\n\nThere are two teardown races to close:\n\n  * rtl8xxxu_queue_rx_urb() decided whether to enqueue under rx_urb_lock\n    but called schedule_work() after dropping the lock.  A completion\n    that observed shutdown == false and released the lock could then call\n    schedule_work() after rtl8xxxu_stop() had set shutdown and\n    cancel_work_sync() had already returned, arming the worker to run\n    after the teardown.  Move schedule_work() under the same !shutdown\n    branch so the arming decision is atomic with the shutdown check.\n\n  * rtl8xxxu_rx_urb_work() anchors every URB it drained back onto\n    rx_anchor through rtl8xxxu_submit_rx_urb().  A worker still running\n    when usb_kill_anchored_urbs(&priv->rx_anchor) returned would submit a\n    URB that escaped the kill.  In rtl8xxxu_stop(), call\n    cancel_work_sync(&priv->rx_urb_wq) before the kill so the worker is\n    drained first.\n\nAfter priv->shutdown is set under rx_urb_lock, completions can no longer\nqueue rx_urb_wq. cancel_work_sync() then drains the last queued or running\nworker, and the following usb_kill_anchored_urbs() kills the URBs it may\nhave submitted.\n\nrtl8xxxu_disconnect() is covered because ieee80211_unregister_hw()\nguarantees .stop() runs for a live interface before ieee80211_free_hw()\nfrees priv.  The probe error path needs no cancel: rx_urb_wq is\nINIT_WORK()'d there but cannot have been scheduled, since no URB is\nsubmitted before ieee80211_register_hw() succeeds.\n\nThis bug was found by static analysis.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":[],"references":["https://git.kernel.org/stable/c/17d5ae58973122eea7625a87cd3d80a8beb23b47","https://git.kernel.org/stable/c/620acb1e8037b73a457dc8ef20fc23fc7adcb405","https://git.kernel.org/stable/c/6c080026ecc17eecb103f8927c64ea73a74bb818","https://git.kernel.org/stable/c/800d2b490a9af1e7132a3564c2ad5a81292e5b40","https://git.kernel.org/stable/c/972ab8b9c08f3eb3fa535082de2950dd93604dfd"],"products":[],"source":"nvd","synced_at":"2026-10-22T16:41:11.231219466+00:00"},"epss":{"cve":"CVE-2026-80947","score":0.00164,"percentile":0.05538,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}