usbip: vudc: fix NULL deref in vep_dequeue()
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-476.
Summary
In the Linux kernel, the following vulnerability has been resolved: usbip: vudc: fix NULL deref in vep_dequeue() vep_alloc_request() wasn't initializing vrequest->udc, so cancellations on the FunctionFS AIO path were arriving in vep_dequeue without a valid UDC reference. Since vrequest->udc is never actually properly used anywhere, we opt to remove it, and update vep_dequeue to obtain a reference to the udc with ep_to_vudc(), consistent with the other vep_ ops. AFAICT this bug has existed for ~10 years. Seems that nobody has really stressed the FunctionFS AIO path on usbip's vudc. I tested this fix in a QEMU aarch64 guest driving FunctionFS endpoints via AIO. Before the fix, running `usbip attach` from the host would cause the guest to oops with the following backtrace: Call trace: vep_dequeue+0x1c/0xe4 (P) usb_ep_dequeue+0x14/0x20 ffs_aio_cancel+0x24/0x34 __arm64_sys_io_cancel+0xb0/0x124 do_el0_svc+0x68/0x100 el0_svc+0x18/0x5c el0t_64_sync_handler+0x98/0xdc el0t_64_sync+0x154/0x158
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 4.7 and later | 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.4, 7.2 | Patch available | CNA |
- Linux VendorLinux Affected 4.7 and later Fixed in 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.4, 7.2 Patch available CNA
CPE configurations NVD · 3
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 4.7 to before 5.10.261; 5.11 to before 5.15.212; 5.16 to before 6.1.178; 6.2 to before 6.6.145; 6.7 to before 6.12.96; 6.13 to before 6.18.39; 6.19 to before 7.1.4 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:* | 7.2 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:7.2:rc2:*:*:*:*:*:* | 7.2 rc2 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.7 to before 5.10.261; 5.11 to before 5.15.212; 5.16 to before 6.1.178; 6.2 to before 6.6.145; 6.7 to before 6.12.96; 6.13 to before 6.18.39; 6.19 to before 7.1.4 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:7.2:rc1:*:*:*:*:*:* Versions 7.2 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:7.2:rc2:*:*:*:*:*:* Versions 7.2 rc2 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.4, 7.2
Vendor assessments
Red Hat
Not affected: 5 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2026-64331
- 2026-10-03 Alias added: GHSA-x846-472j-jj99
- 2026-11-06 CISA SSVC decision points changed
References
Patch 8
- https://git.kernel.org/stable/c/9858c91d9ee6a13c45311569039413729fc9b757
- https://git.kernel.org/stable/c/1226293ec9bed3d4cc5b05eeeb811d315ca51652
- https://git.kernel.org/stable/c/3750f75f29f99c0223601e2ee73ad084adec47bd
- https://git.kernel.org/stable/c/d0ebf9cc7c2ddf95a7cfc654b940bdacb7edde97
- https://git.kernel.org/stable/c/0025276175fbbe0dcbf3f84d090b0adee769e9d9
- https://git.kernel.org/stable/c/347b59e9f96719d89b6ef555d02a18ada1a5846f
- https://git.kernel.org/stable/c/0443e4416aa1ee97748d1ed904eaf3352c60045e
- https://git.kernel.org/stable/c/c5371e0b91b24159a3ebaa61e70b0980bcf03c0a
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2026-64331 · CVE Program
- CVE-2026-64331 · NVD
- FIRST EPSS
- GHSA-x846-472j-jj99 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-64331 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences