{"id":"CVE-2026-98006","published":"2026-09-25T11:17:28.847","lastModified":"2026-09-25T11:17:28.847","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nALSA: caiaq: Decoupling ep1_in_urb in caiaq dev\n\nThe epq_in_urb object belonging to the caiaq device is coupled within\nthe struct snd_usb_caiaqdev. After usb_submit_urb(epq_in_urb, GFP_KERNEL)\nexecutes successfully, epq_in_urb is successfully added to the urbp_list\nqueue of the dummy HCD driver (userspace specifies dummy_hcd as the HCD\nlayer driver for the caiaq USB device).\n\nWhen init_card() calls snd_usb_caiaq_send_command() which subsequently\nfails due to a timeout, and proceeds to call snd_card_free() to release\nthe card, the embedded ep1_in_urb object is also freed. When the dummy\nHCD driver detects that the URB has been unlinked, it returns the URB\n(by usb_hcd_giveback_urb()), which triggers [1].\n\nDecouple the ep1_in_urb object from the struct snd_usb_caiaqdev and switch\nto using a pointer instead. Separately allocate and manage the memory for\nep1_in_urb to prevent the release of the snd_card memory object from\ninterfering with it.\n\nmidi_out_urb has the same issue as ep1_in_urb and is handled in the same\nway.\n\n[1]\nBUG: KASAN: slab-use-after-free in usb_free_urb+0x24/0x120 drivers/usb/core/urb.c:96\nWrite of size 4 at addr ffff88803cee1050 by task ktimers/1/29\nCall Trace:\n usb_free_urb+0x24/0x120 drivers/usb/core/urb.c:96\n dummy_timer+0xaac/0x4d50 drivers/usb/gadget/udc/dummy_hcd.c:2019\n __run_hrtimer kernel/time/hrtimer.c:2067 [inline]\n __hrtimer_run_queues+0x3eb/0xaf0 kernel/time/hrtimer.c:2124\n hrtimer_run_softirq+0x1e1/0x2e0 kernel/time/hrtimer.c:2141\n\nAllocated by task 36:\n snd_card_new+0x7b/0x110 sound/core/init.c:184\n create_card sound/usb/caiaq/device.c:429 [inline]\n snd_probe+0x236/0x1af0 sound/usb/caiaq/device.c:544\n\nFreed by task 36:\n snd_card_free_when_closed sound/core/init.c:630 [inline]\n snd_card_free+0x138/0x1d0 sound/core/init.c:662\n snd_probe+0x162b/0x1af0 sound/usb/caiaq/device.c:553","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/0c1b907d5db2f3508375776e5b78d69591aa5626","tags":[]},{"url":"https://git.kernel.org/stable/c/402a9d6aab7ac787ab075adeb562c3db8b8f564b","tags":[]},{"url":"https://git.kernel.org/stable/c/d41e6c1533f09b27fc562260d41417490d2b6084","tags":[]},{"url":"https://git.kernel.org/stable/c/d6dd3c915b0d02457711d8fbaa60efc52144557f","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}