CVE-2026-80824

CVE CVE-2026-80824EUVD EUVD-2026-71274Veröffentlicht 2026-09-04T15:54:28.000Z

Was das Advisory beschreibt

In the Linux kernel, the following vulnerability has been resolved: usb: usbfs: fix use-after-free of usb_device in usbdev_release() usbdev_release() drops its reference to the struct usb_device before draining the list of completed async URBs, but that drain path reads back through the same object: free_async() calls dec_usb_memory_use_count() for any URB whose buffer came from the usbfs mmap() region, and its first statement is bus_to_hcd(ps->dev->bus). After a disconnect the usbfs reference can be the last one, in which case usb_put_dev() frees the device and the subsequent loop reads offset 80 of freed memory and uses the result as a struct usb_hcd *, which hcd_buffer_free_pages() then dereferences. This is reachable by an unprivileged process that has read/write access to a /dev/bus/usb node: mmap() the fd, submit one URB with a buffer inside the mapping, wait for the device to be unplugged, then munmap() and close(). It reproduces on every attempt rather than being a race, because a live MAP_SHARED vma holds a reference on the struct file, so usbdev_release() cannot run until the last vma is gone and the freeing branch of dec_usb_memory_use_count() is always taken. BUG: KASAN: slab-use-after-free in dec_usb_memory_use_count+0x3ae/0x410 Read of size 8 at addr ffff8880122ee050 by task poc/769 CPU: 1 UID: 1000 PID: 769 Comm: poc Tainted: G B 6.12.94 #3 Call Trace: dec_usb_memory_use_count+0x3ae/0x410 free_async+0x2aa/0x4f0 usbdev_release+0x375/0x460 __fput+0x3ea/0xb50 __x64_sys_close+0x86/0x100 Allocated by task 11: usb_alloc_dev+0x55/0xd90 hub_event+0x2524/0x43d0 Freed by task 769: kfree+0x121/0x360 device_release+0xd2/0x280 usb_put_dev+0x23/0x30 usbdev_release+0x2d8/0x460 Release the device reference after the drain loop instead. Nothing between the two points requires it to have been dropped.

Quelle: EUVD (ENISA), im Wortlaut der Meldung.

Produkte, die das Advisory nennt

Diese Angaben stammen aus der Meldung selbst, nicht aus einer Prüfung durch uns.

• Linux — Linux patch: 6.12.108; f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 <65879e0a452ca2a234b9475e0c11aff7a4343738; f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 <47a7f98fbb5006d46d15a3a210ffdc61448a4f19; patch: 6.1.187; patch: 6.18.49; patch: 7.1.13; f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 <bd4bffc621a8cb2f4d9ed9b6447415de524a3bef; patch: 7.2.3; patch: 7.3-rc1; patch: 5.15.220; f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 <0dd68b5d01d022fc9c5e71c82a82b0a94d3d0671; 4.6; patch: 6.6.156; f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 <96f5520fc9a5e4bbf77ac93c9d5ce502f597e6cf; patch: 0; f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 <7f0278e474c4d1c4457974ff1137cc385c944ab3; patch: 5.10.269; f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 <b3cde26a66b04f1d90ed0b675899c88b4e49d424; f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 <5f08c45bdcfd28d1171de38c5ef29fc89a76eedc; f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 <0a960b88c5979f853019d4dc4957dfbeeb193440

Die genannten Versionen sind die Angabe der Meldung. Patchlage vergleicht keine Versionsnummern und leitet aus ihnen keine Aussage ab — welche Version installiert ist, muss ein Mensch nachsehen.

Im Produktkatalog geführt

Für diese Produkte kann ein Bestand in Patchlage erfasst werden. Ein Advisory dazu erscheint am Morgen danach im Lagebericht.

• Linux — Linux

Patchlage meldet Treffer und Verdachtsfälle. Zu allem anderen sagt dieses System nichts — weder diese Seite noch der Lagebericht behauptet je, dass ein Bestand sicher ist.