{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-80947", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-26T14:34:25.803Z", "datePublished": "2026-09-11T19:42:18.282Z", "dateUpdated": "2026-10-21T12:47:17.715Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-21T12:47:17.715Z" }, "descriptions": [ { "lang": "en", "value": "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." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The UAF is reached when rtl8xxxu_stop()/rtl8xxxu_disconnect() runs while rx_urb_wq is armed. An adjacent Wi-Fi peer can complete RX URBs and queue the work, but cannot invoke stop or ieee80211_free_hw(); teardown is a local action (interface down, rfkill, suspend, USB unbind or unplug).\nAC:L - The attacker controls both sides of the race: they generate RX traffic so rx_urb_pending_count exceeds RTL8XXXU_RX_URB_PENDING_WATER (8) and schedule_work(&rx_urb_wq) fires, then they trigger stop/disconnect while the worker is queued or still resubmitting URBs, retrying until the window after ieee80211_free_hw() is hit.\nPR:L - An ordinary local user can trigger teardown via logind-mediated suspend, rfkill, or USB unplug on a shared workstation, and needs no capability to generate the RX traffic that queues rx_urb_wq. CAP_NET_ADMIN to bring the interface down is also available via user namespaces when the wiphy is delegated into that netns.\nUI:N - The attacker generates the RX burst and performs the interface stop or USB disconnect themselves; no separate victim must open a file, mount a filesystem, or otherwise interact.\nS:U - The use-after-free corrupts the rtl8xxxu_priv kernel object and USB URB state inside the host kernel; it does not cross a VM, IOMMU, or sandbox boundary.\nC:H - rtl8xxxu_rx_urb_work() recovers the freed priv via container_of and reads priv->udev, priv->fops, and pending-list/rx_anchor state. A sprayed replacement slab object therefore yields an arbitrary kernel read primitive.\nI:H - The worker list_splice_init()s the freed pending list, usb_anchor_urb()s onto priv->rx_anchor, and the workqueue core mutates the embedded work_struct inside the freed priv, giving heap-write and control-flow hijack primitives.\nA:H - Executing rtl8xxxu_rx_urb_work() against freed priv oopses or panics on the spinlock, list, or udev dereference, and the attacker can retrigger it on every device stop or USB disconnect." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/wireless/realtek/rtl8xxxu/core.c" ], "versions": [ { "version": "26f1fad29ad973b0fb26a9ca3dcb2a73dde781aa", "lessThan": "17d5ae58973122eea7625a87cd3d80a8beb23b47", "status": "affected", "versionType": "git" }, { "version": "26f1fad29ad973b0fb26a9ca3dcb2a73dde781aa", "lessThan": "800d2b490a9af1e7132a3564c2ad5a81292e5b40", "status": "affected", "versionType": "git" }, { "version": "26f1fad29ad973b0fb26a9ca3dcb2a73dde781aa", "lessThan": "620acb1e8037b73a457dc8ef20fc23fc7adcb405", "status": "affected", "versionType": "git" }, { "version": "26f1fad29ad973b0fb26a9ca3dcb2a73dde781aa", "lessThan": "972ab8b9c08f3eb3fa535082de2950dd93604dfd", "status": "affected", "versionType": "git" }, { "version": "26f1fad29ad973b0fb26a9ca3dcb2a73dde781aa", "lessThan": "6c080026ecc17eecb103f8927c64ea73a74bb818", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/wireless/realtek/rtl8xxxu/core.c" ], "versions": [ { "version": "4.4", "status": "affected" }, { "version": "0", "lessThan": "4.4", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.109", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.50", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.4", "versionEndExcluding": "6.6.160" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.4", "versionEndExcluding": "6.12.109" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.4", "versionEndExcluding": "6.18.50" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.4", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.4", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/17d5ae58973122eea7625a87cd3d80a8beb23b47" }, { "url": "https://git.kernel.org/stable/c/800d2b490a9af1e7132a3564c2ad5a81292e5b40" }, { "url": "https://git.kernel.org/stable/c/620acb1e8037b73a457dc8ef20fc23fc7adcb405" }, { "url": "https://git.kernel.org/stable/c/972ab8b9c08f3eb3fa535082de2950dd93604dfd" }, { "url": "https://git.kernel.org/stable/c/6c080026ecc17eecb103f8927c64ea73a74bb818" } ], "title": "wifi: rtl8xxxu: fix use-after-free from rx_urb_wq on stop", "x_generator": { "engine": "bippy-1.2.0" } } } }