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PatchSiren cyber security CVE debrief

CVE-2026-64051 Linux CVE debrief

A vulnerability was found in the Linux kernel, specifically in the qaic_gem_object_mmap function, which is susceptible to (re)mapping beyond the VMA if the BO is too large. This can cause use after free issues when munmap() unmaps only the VMA region and not the additional mappings. The vulnerability has been resolved by adding an overflow check to remap_pfn_range during mmap. Linux kernel users and administrators should be aware of this vulnerability and take necessary actions to protect their systems.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-19
Original CVE updated
2026-07-19
Advisory published
2026-07-19
Advisory updated
2026-07-19

Who should care

Linux kernel users and administrators should be aware of this vulnerability and take necessary actions to protect their systems. They should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. They should also plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.

Technical summary

The vulnerability is caused by a lack of overflow check in the remap_pfn_range function during mmap. This can lead to use after free issues when munmap() is called. To prevent this, a check for the remaining size of the VMA before remapping and truncate the remapped length if sg->length is too large is necessary. The fix involves adding an overflow check to remap_pfn_range during mmap to prevent use after free issues.

Defensive priority

High

Recommended defensive actions

  • Apply the patch to add an overflow check to remap_pfn_range during mmap
  • Verify and apply Linux kernel updates
  • Monitor system logs for potential use after free issues
  • 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 2026-07-19T16:17:45.517Z and has not been modified since then. The NVD entry is currently Received. There is limited information available about the vulnerability, and defenders should verify the affected scope and severity with the official advisory. The Linux kernel vulnerability is related to the qaic_gem_object_mmap function, which requires an overflow check to prevent use after free issues.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-19T16:17:45.517Z and has not been modified since then.