CVE-2026-80824

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

What the advisory describes

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.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

• 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

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

• Linux — Linux

Patchlage reports hits and suspected hits. About everything else this system says nothing — neither this page nor the situation report ever claims that an estate is safe.