CVE intelligence

CVE-2026-63623

Vulnerability intelligence

Published Aug 10, 2026Sources checked Sep 12, 2026

5.5MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-63623 and is rated Medium severity with a CVSS score of 5.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.1%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-63623?

A flaw was found in libvirt. During storage volume clone or convert operations, newly created volume images were temporarily world-readable. This was caused by the `qemu-img` utility running with overly permissive file creation settings, allowing any local user to read the full guest disk contents. This vulnerability could lead to sensitive information disclosure from guest virtual machines.