CVE-2026-64331

Guest crash via uninitialized vUDC request pointer

Published Jul 25, 2026 · Updated Jul 25, 2026

NULL pointer dereference in Linux Kernel usbip vUDC allows local users to crash a guest via FunctionFS AIO request cancellation. vep_alloc_request leaves vrequest->udc uninitialized, and vep_dequeue dereferences that invalid UDC reference when an AIO request is canceled. The crash requires a guest using usbip vUDC with FunctionFS endpoints driven through AIO; a host usbip attach operation can trigger the guest kernel oops.

CVSS severityUnavailable
Unscored
EPSS probability0.12%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

NULL pointer dereference in Linux Kernel usbip vUDC allows local users to crash a guest via FunctionFS AIO request cancellation. vep_alloc_request leaves vrequest->udc uninitialized, and vep_dequeue dereferences that invalid UDC reference when an AIO request is canceled. The crash requires a guest using usbip vUDC with FunctionFS endpoints driven through AIO; a host usbip attach operation can trigger the guest kernel oops.

The record

CVE
CVE-2026-64331
Published
Jul 25, 2026
Updated
Jul 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
local
Privileges
Unavailable

Timeline

How it unfolded

  1. Jul 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.7
  2. Affected versionversion=b6a0ca11186759ad7045d68a5447b1e89f658384 <0025276175fbbe0dcbf3f84d090b0adee769e9d9
  3. Affected versionversion=b6a0ca11186759ad7045d68a5447b1e89f658384 <0443e4416aa1ee97748d1ed904eaf3352c60045e
  4. Affected versionversion=b6a0ca11186759ad7045d68a5447b1e89f658384 <1226293ec9bed3d4cc5b05eeeb811d315ca51652
  5. Affected versionversion=b6a0ca11186759ad7045d68a5447b1e89f658384 <347b59e9f96719d89b6ef555d02a18ada1a5846f
  6. Affected versionversion=b6a0ca11186759ad7045d68a5447b1e89f658384 <3750f75f29f99c0223601e2ee73ad084adec47bd
  7. Affected versionversion=b6a0ca11186759ad7045d68a5447b1e89f658384 <9858c91d9ee6a13c45311569039413729fc9b757
  8. Affected versionversion=b6a0ca11186759ad7045d68a5447b1e89f658384 <c5371e0b91b24159a3ebaa61e70b0980bcf03c0a
  9. Affected versionversion=b6a0ca11186759ad7045d68a5447b1e89f658384 <d0ebf9cc7c2ddf95a7cfc654b940bdacb7edde97

What conditions does exploitation require?

Attack vectorlocal
Required privilegesUnavailable in this record.

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.7; version=b6a0ca11186759ad7045d68a5447b1e89f658384 <0025276175fbbe0dcbf3f84d090b0adee769e9d9; version=b6a0ca11186759ad7045d68a5447b1e89f658384 <0443e4416aa1ee97748d1ed904eaf3352c60045e; version=b6a0ca11186759ad7045d68a5447b1e89f658384 <1226293ec9bed3d4cc5b05eeeb811d315ca51652; version=b6a0ca11186759ad7045d68a5447b1e89f658384 <347b59e9f96719d89b6ef555d02a18ada1a5846f; version=b6a0ca11186759ad7045d68a5447b1e89f658384 <3750f75f29f99c0223601e2ee73ad084adec47bd; version=b6a0ca11186759ad7045d68a5447b1e89f658384 <9858c91d9ee6a13c45311569039413729fc9b757; version=b6a0ca11186759ad7045d68a5447b1e89f658384 <c5371e0b91b24159a3ebaa61e70b0980bcf03c0a; version=b6a0ca11186759ad7045d68a5447b1e89f658384 <d0ebf9cc7c2ddf95a7cfc654b940bdacb7edde97

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo