CVE intelligence

CVE-2026-18917

Vulnerability intelligence

Published Aug 20, 2026Sources checked Oct 28, 2026

7.8HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-18917 and is rated High severity with a CVSS score of 7.8. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Sep 13, 2026

See the Microsoft Security Update Guide for the update that applies to your product.

Vendor-listed releases

11.9.0-1

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-18917?

A flaw was found in libvirt. An unprivileged local user could exploit an integer overflow vulnerability in the NodeGetFreePages RPC handler.

This flaw allows crafted values to bypass a size check, leading to an undersized memory buffer. Subsequently, real NUMA node data can overwrite this buffer.

This heap buffer overflow can corrupt the root libvirt daemon's memory, potentially leading to a denial of service or local privilege escalation.

Source: NVD