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CVE-2026-64346 Linux CVE debrief

A Use-After-Free vulnerability was discovered in the Linux kernel's USB gadget subsystem. The vulnerability occurs when the udc structure is freed while still being accessed by the gadget_match_driver function, leading to a NULL pointer dereference. This issue arises from a race condition between usb_del_gadget and gadget_match_driver functions. The vulnerability impacts Linux kernel developers, maintainers, and users of Linux-based systems.

Vendor
Linux
Product
Unknown
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-25
Original CVE updated
2026-09-03
Advisory published
2026-07-25
Advisory updated
2026-09-03

Who should care

Linux kernel developers and maintainers, as well as users of Linux-based systems, should be aware of this vulnerability and take steps to mitigate it. This includes reviewing Linux kernel versions, applying patches, and monitoring for future updates related to this vulnerability.

Technical summary

The vulnerability is caused by a race condition between the usb_del_gadget function and the gadget_match_driver function. The usb_del_gadget function frees the udc memory, while the gadget_match_driver function accesses the freed memory, leading to a Use-After-Free vulnerability. The patch introduces a new usb_gadget_release routine to ensure the udc structure remains allocated until the gadget is released.

Defensive priority

High

Recommended defensive actions

  • Apply the patch to the Linux kernel to fix the vulnerability
  • Use a Linux kernel version that has the patch applied
  • Monitor Linux kernel updates for future patches related to this vulnerability
  • Review compensating controls for exposed systems while remediation is scheduled and verified
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability was discovered and patched in the Linux kernel. The patch introduces a new usb_gadget_release routine to ensure the udc structure remains allocated until the gadget is released. Evidence is limited to CVE and NVD details. Defenders should verify Linux kernel versions, review configfs and USB gadget interactions, and monitor for related updates.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-64346 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-64346

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-64346 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-64346

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/50eeb8e8a4f389efc91b93cff14a683e714ec194

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/54fa390aae393eb130f307a85562e3001cc39a52

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/67e511d2989eb1c8c588b599ce2fcc6bb8e6f7ea

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/7a5214dae906d9f58e07bc4995e8181ee74439f4

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/b52476a83d9e12df00765359d728a875b128bef1

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/d026f71df141c9b064ff32a78af5391a31ef75c2

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/f845852a5a8914277031f47d8de0f350fef52405

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.