Linux Kernel up to 7.2-rc2 usbip vep_dequeue udc null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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6.2$0-$5k3.19

Summaryinfo

A vulnerability was found in Linux Kernel up to 7.2-rc2 and classified as critical. This impacts the function vep_dequeue of the component usbip. Executing a manipulation of the argument udc can lead to null pointer dereference. This vulnerability appears as CVE-2026-64331. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.2-rc2. It has been declared as critical. This vulnerability affects the function vep_dequeue of the component usbip. The manipulation of the argument udc with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. CVE summarizes:

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

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2026-64331 since 07/19/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/25/2026).

Upgrading to version 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.4 or 7.2-rc3 eliminates this vulnerability. Applying the patch 9858c91d9ee6a13c45311569039413729fc9b757/1226293ec9bed3d4cc5b05eeeb811d315ca51652/3750f75f29f99c0223601e2ee73ad084adec47bd/d0ebf9cc7c2ddf95a7cfc654b940bdacb7edde97/0025276175fbbe0dcbf3f84d090b0adee769e9d9/347b59e9f96719d89b6ef555d02a18ada1a5846f/0443e4416aa1ee97748d1ed904eaf3352c60045e/c5371e0b91b24159a3ebaa61e70b0980bcf03c0a is able to eliminate this problem.

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Productinfo

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Version

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.261/5.15.212/6.1.178/6.6.145/6.12.96/6.18.39/7.1.4/7.2-rc3
Patch: 9858c91d9ee6a13c45311569039413729fc9b757/1226293ec9bed3d4cc5b05eeeb811d315ca51652/3750f75f29f99c0223601e2ee73ad084adec47bd/d0ebf9cc7c2ddf95a7cfc654b940bdacb7edde97/0025276175fbbe0dcbf3f84d090b0adee769e9d9/347b59e9f96719d89b6ef555d02a18ada1a5846f/0443e4416aa1ee97748d1ed904eaf3352c60045e/c5371e0b91b24159a3ebaa61e70b0980bcf03c0a

Timelineinfo

07/19/2026 CVE reserved
07/25/2026 +6 days Advisory disclosed
07/25/2026 +0 days VulDB entry created
07/25/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64331 (🔒)
GCVE (CVE): GCVE-0-2026-64331
GCVE (VulDB): GCVE-100-383128

Entryinfo

Created: 07/25/2026 15:41
Changes: 07/25/2026 15:41 (60)
Complete: 🔍
Cache ID: 216::103

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