CVE-2026-64524 Linux CVE debrief

Who should care

Linux kernel administrators and developers using the drm/hyperv module should assess their exposure and prioritize patching. Affected systems should be patched as soon as possible to prevent potential denial of service and elevation of privileges. The vulnerability can be exploited by parsing a SYNTHVID_RESOLUTION_RESPONSE with a resolution_count greater than 64, causing the code to access an array out of bounds.

Why it matters

The CVE-2026-64524 vulnerability in the Linux kernel's drm/hyperv module requires attention from Linux kernel administrators and developers. The vulnerability can lead to a denial of service and potential elevation of privileges. Affected systems should be patched as soon as possible.

• Potential denial of service due to rejection of userspace framebuffers
• Possible elevation of privileges through exploitation of the out-of-bounds array access

Technical summary

The vulnerability occurs in the Linux kernel's drm/hyperv module, specifically in the handling of SYNTHVID_RESOLUTION_RESPONSE packets. A resolution_count greater than 64 can cause an out-of-bounds array access. Additionally, when the WIN10 resolution probe fails, certain fields are not populated, leading to a rejection of every userspace framebuffer with -EINVAL. Linux kernel administrators and developers using the drm/hyperv module should assess their exposure and prioritize patching. The vulnerability can lead to a denial of service and potential elevation of privileges.

Defensive priority

Assess exposure and prioritize patching for Linux kernel deployments using the drm/hyperv module.

Recommended defensive actions

• Assess Linux kernel deployments for exposure to the drm/hyperv module
• Prioritize patching for affected systems
• Verify the integrity of the drm/hyperv module
• 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 and NVD vulnerability detail page provide information on the vulnerability, including its description and CVSS score. Linux kernel administrators and developers should verify the integrity of the drm/hyperv module and assess their exposure to this vulnerability. The vulnerability occurs in the Linux kernel's drm/hyperv module, specifically in the handling of SYNTHVID_RESOLUTION_RESPONSE packets. A resolution_count greater than 64 can cause an out-of-bounds array access. Additionally, when the WIN10 resolution probe

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.