{"id":"CVE-2026-68363","title":"wifi: ath9k: hif_usb: don't dereference hif_dev after re-arming firmware request","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: ath9k: hif_usb: don't dereference hif_dev after re-arming firmware request\n\nath9k_hif_request_firmware() re-arms an asynchronous firmware load via\nrequest_firmwar…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 47ed81aaa7f94d9808f4719e78a760c2ec1e6c86","Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 48de0c6952192b0771fca468df4364d11ec74ad9","Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 063497cc9f320ab71a7a937c3bc0a23e630aefe2","Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 7f184ca38a90889f3f6665ff96748b95da39dbee","Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 10b0ce629123a3737b4eda50188f73bb7be7b68b","Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 48a69cedde7388294e4ea6fd804156cd62bc04fc","Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 7c9046d92c4b9789c9d9d775e4fd5f34be64cb0a","Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < dad9f96945d77ecd4708f730c06ef54dcd8cc057","Linux 4.4"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-06T16:48:07.946520Z"},"published":"2026-08-10","updated":"2026-11-06","sourceUpdated":"2026-11-06T16:55:14.386Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-68363","references":[{"url":"https://git.kernel.org/stable/c/47ed81aaa7f94d9808f4719e78a760c2ec1e6c86"},{"url":"https://git.kernel.org/stable/c/48de0c6952192b0771fca468df4364d11ec74ad9"},{"url":"https://git.kernel.org/stable/c/063497cc9f320ab71a7a937c3bc0a23e630aefe2"},{"url":"https://git.kernel.org/stable/c/7f184ca38a90889f3f6665ff96748b95da39dbee"},{"url":"https://git.kernel.org/stable/c/10b0ce629123a3737b4eda50188f73bb7be7b68b"},{"url":"https://git.kernel.org/stable/c/48a69cedde7388294e4ea6fd804156cd62bc04fc"},{"url":"https://git.kernel.org/stable/c/7c9046d92c4b9789c9d9d775e4fd5f34be64cb0a"},{"url":"https://git.kernel.org/stable/c/dad9f96945d77ecd4708f730c06ef54dcd8cc057"}],"tags":["cve.org"],"epss":0.00184,"epssPercentile":0.08082,"ingestedAt":"2026-11-06T18:00:12.607Z","slug":"CVE-2026-68363","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nwifi: ath9k: hif_usb: don't dereference hif_dev after re-arming firmware request\n\nath9k_hif_request_firmware() re-arms an asynchronous firmware load via\nrequest_firmware_nowait(), passing hif_dev as the completion context, and\nthen still dereferences hif_dev:\n\n\tdev_info(&hif_dev->udev->dev, \"ath9k_htc: Firmware %s requested\\n\",\n\t\t hif_dev->fw_name);\n\nThe re-armed callback ath9k_hif_usb_firmware_cb() runs on the \"events\"\nworkqueue and, when the firmware is missing, walks the retry chain into\nath9k_hif_usb_firmware_fail() -> complete_all(&hif_dev->fw_done). That\nreleases the wait_for_completion(&hif_dev->fw_done) in a concurrent\nath9k_hif_usb_disconnect(), which then kfree()s hif_dev. The trailing\ndev_info() in the frame that re-armed the request can therefore read freed\nmemory (hif_dev->udev, the first field of struct hif_device_usb):\n\n  BUG: KASAN: slab-use-after-free in ath9k_hif_request_firmware\n  Read of size 8 ... by task kworker/...\n   ath9k_hif_request_firmware\n   ath9k_hif_usb_firmware_cb           drivers/net/wireless/ath/ath9k/hif_usb.c:1247\n   request_firmware_work_func\n  Allocated by ...:\n   ath9k_hif_usb_probe                 drivers/net/wireless/ath/ath9k/hif_usb.c\n  Freed by ...:\n   ath9k_hif_usb_disconnect -> kfree   drivers/net/wireless/ath/ath9k/hif_usb.c\n\nThe fw_done barrier only makes disconnect wait for the firmware chain to\n*terminate*; it does not protect the outer ath9k_hif_request_firmware()\nframe that re-armed the request and keeps touching hif_dev afterwards.\n\nDrop the post-request dev_info(): it is the only use of hif_dev after the\nasync request is armed, and it is purely informational (the dev_err() on the\nfailure path runs only when request_firmware_nowait() did not arm a callback,\nso hif_dev is still alive there).\n\nThis was first reported by syzbot as a single, non-reproduced crash that was\nlater auto-obsoleted, and was independently rediscovered by the reFuzz fuzzer,\nwhich produced a C reproducer (USB-gadget connect/disconnect of an ath9k_htc\ndevice whose firmware download fails). The vulnerable code is unchanged and\nstill present in v7.1-rc6, where the slab-use-after-free reproduces under KASAN\nonce the (sub-microsecond) race window is widened.\n\n## Affected\n\n- `Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 47ed81aaa7f94d9808f4719e78a760c2ec1e6c86`\n- `Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 48de0c6952192b0771fca468df4364d11ec74ad9`\n- `Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 063497cc9f320ab71a7a937c3bc0a23e630aefe2`\n- `Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 7f184ca38a90889f3f6665ff96748b95da39dbee`\n- `Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 10b0ce629123a3737b4eda50188f73bb7be7b68b`\n- `Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 48a69cedde7388294e4ea6fd804156cd62bc04fc`\n- `Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < 7c9046d92c4b9789c9d9d775e4fd5f34be64cb0a`\n- `Linux >= e904cf6fe23022cde4e0ea9d41601411a315a3dc < dad9f96945d77ecd4708f730c06ef54dcd8cc057`\n- `Linux 4.4`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}