CVE-2026-64455 Linux CVE debrief

Who should care

Linux kernel developers and maintainers, Linux distribution maintainers, and users of the Linux kernel with the chaoskey driver enabled should care about this vulnerability as it can cause a denial of service (DoS) and requires verification of patch application and fix effectiveness.

Why it matters

A use-after-free vulnerability in the Linux kernel's chaoskey driver can lead to a denial of service (DoS) and requires verification of patch application and fix effectiveness.

• Potential denial of service (DoS) due to slab-use-after-free error
• Verification of patch application and fix effectiveness is necessary

Technical summary

The Linux kernel's chaoskey driver has a use-after-free bug in its release routine. When the user closes the device file after the USB device has been unplugged, a debugging log statement attempts to access the usb_interface structure after it has been deallocated, leading to a slab-use-after-free error. The fix involves removing the debugging log statement that accesses the usb_interface structure after it has been deallocated. This fix prevents the slab-use-after-free error and potential denial of service (DoS). The Linux kernel developers and maintainers, Linux distribution maintainers, and users of the Linux kernel with the chaoskey driver enabled should verify the patch application and fix effectiveness.

Defensive priority

Medium

Recommended defensive actions

• Review and apply the patch to the Linux kernel
• Verify the fix in the Linux kernel
• Monitor for potential exploitation attempts
• Perform a thorough review of the Linux kernel's chaoskey driver to identify potential similar vulnerabilities
• 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 resolved by removing the debugging log statement that accesses the usb_interface structure after it has been deallocated. This fix prevents the slab-use-after-free error. The patch should be reviewed and applied to the Linux kernel, and the fix effectiveness should be verified. The Linux kernel developers and maintainers, Linux distribution maintainers, and users of the Linux kernel with the chaoskey driver enabled should care about this vulnerability.

Sources and references

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.