CVE-2026-80824usb: usbfs: fix use-after-free of usb_device in usbdev_release()
- —Not scoredno CVSS score yet
- 0.19%Exploitation in 30 daysEPSS · top 91% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By Linux
- 9 days later
· 9 days later
Published
- 45 days later
· 45 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.19% · top 91% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 – < 0a960b88c5979f853019d4dc4957dfbeeb193440
- affected f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 – < 96f5520fc9a5e4bbf77ac93c9d5ce502f597e6cf
- affected f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 – < bd4bffc621a8cb2f4d9ed9b6447415de524a3bef
- affected f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 – < 65879e0a452ca2a234b9475e0c11aff7a4343738
- affected f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 – < b3cde26a66b04f1d90ed0b675899c88b4e49d424
- affected f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 – < 5f08c45bdcfd28d1171de38c5ef29fc89a76eedc
- affected f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 – < 7f0278e474c4d1c4457974ff1137cc385c944ab3
- affected f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 – < 47a7f98fbb5006d46d15a3a210ffdc61448a4f19
- affected f7d34b445abc00e979b7cf36b9580ac3d1a47cd8 – < 0dd68b5d01d022fc9c5e71c82a82b0a94d3d0671
- affected 4.6
- unaffected < 4.6
- unaffected 5.10.269 – ≤ 5.10.*
- unaffected 5.15.220 – ≤ 5.15.*
- unaffected 6.1.187 – ≤ 6.1.*
- unaffected 6.6.156 – ≤ 6.6.*
- unaffected 6.12.108 – ≤ 6.12.*
- unaffected 6.18.49 – ≤ 6.18.*
- unaffected 7.1.13 – ≤ 7.1.*
- unaffected 7.2.3 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References9
- https://git.kernel.org/stable/c/0a960b88c5979f853019d4dc4957dfbeeb193440 (opens in a new tab)
- https://git.kernel.org/stable/c/96f5520fc9a5e4bbf77ac93c9d5ce502f597e6cf (opens in a new tab)
- https://git.kernel.org/stable/c/bd4bffc621a8cb2f4d9ed9b6447415de524a3bef (opens in a new tab)
- https://git.kernel.org/stable/c/65879e0a452ca2a234b9475e0c11aff7a4343738 (opens in a new tab)
- https://git.kernel.org/stable/c/b3cde26a66b04f1d90ed0b675899c88b4e49d424 (opens in a new tab)
- https://git.kernel.org/stable/c/5f08c45bdcfd28d1171de38c5ef29fc89a76eedc (opens in a new tab)
- https://git.kernel.org/stable/c/7f0278e474c4d1c4457974ff1137cc385c944ab3 (opens in a new tab)
- https://git.kernel.org/stable/c/47a7f98fbb5006d46d15a3a210ffdc61448a4f19 (opens in a new tab)
- https://git.kernel.org/stable/c/0dd68b5d01d022fc9c5e71c82a82b0a94d3d0671 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-71274 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-80824)Record last updated .