CVE-2026-64047 Linux CVE debrief

Who should care

Linux kernel maintainers, Linux distribution vendors, and users of Linux kernel versions affected by this vulnerability should be aware of this issue and take necessary actions to update their kernels. This includes reviewing and applying patches from Linux kernel maintainers, monitoring Linux kernel updates and security advisories, and tracking exceptions and retesting remediated assets.

Technical summary

The Linux kernel vulnerability CVE-2026-64047 was caused by an off-by-one error in sg_chain entry count for wrapped sk_msg ring. The sg_chain() function was called with an incorrect ring size, leading to the chain pointer being placed at an incorrect position. This issue was resolved by converting to ARRAY_SIZE and dropping the data[start] / - start calculation. The affected product context is Linux kernel versions, and the defensive impact is related to updating Linux kernel to the latest version.

Defensive priority

Medium

Recommended defensive actions

• Update Linux kernel to the latest version
• Review and apply patches from Linux kernel maintainers
• Monitor Linux kernel updates and security advisories
• 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 CVE record was published on 2026-07-19T16:17:45.053Z and has not been modified since then. The NVD entry is currently Received. There is limited information available about this vulnerability, and defenders should verify the affected scope and severity with the official advisory or CVE record.

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.