CVE-2026-64251 Linux CVE debrief

Who should care

Linux kernel developers, users, and security teams should be aware of this vulnerability and ensure they are using the patched version of the kernel. They should review and update Linux kernel configurations to ensure the fix is applied and monitor Linux kernel updates for future patches and security advisories.

Technical summary

The vulnerability is caused by the use of __free(put_device) in pwrseq_debugfs_seq_next(), which leads to a use-after-free when the seq_file framework receives a pointer whose reference has already been dropped. To fix this, the reference counting was made consistent across all seq_file callbacks, matching the standard pattern used by PCI and SCSI. This fix prevents the use-after-free vulnerability and ensures the stability of the Linux kernel.

Defensive priority

High

Recommended defensive actions

• Apply the patch to update the Linux kernel to the latest version
• Review and update Linux kernel configurations to ensure the fix is applied
• Monitor Linux kernel updates for future patches and security advisories
• Verify the Linux kernel version and configurations
• Check for exposed assets that need extra review
• Track exceptions and retest remediated assets

Evidence notes

The CVE record was published on 2026-07-24T16:16:54.713Z and was last modified on 2026-07-27T05:16:37.683Z. The NVD entry is currently Received. Linux kernel developers should verify the patched version and ensure it is applied correctly. Defensive verification tasks include reviewing the Linux kernel configurations and monitoring updates for future patches and security advisories.

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.