# CVE-2026-63623: Libvirt: information disclosure via world-readable storage volume images during clone/convert

Status: published. Published: 2026-08-10. Updated: 2026-11-05.

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.

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability. (source: CNA: redhat)

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 10 (libvirt): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (libvirt): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (libvirt): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (virt:rhel/libvirt): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libvirt): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux for NVIDIA 26 (libvirt): Version range not reported. Source: CNA: redhat

## Severity and prioritization

- CVSS 3.1: 5.5 (medium); CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.10% as of 2026-11-05; percentile 0.67%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-732

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/security/cve/CVE-2026-63623 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2513066 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-63623; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-63623; retrieved 2026-11-05; source updated Not reported

Revision: f869499c23774c5c95e712cd4a72933056610c79e2f200f4fee83fad49b94969

Canonical: https://y2.dev/cve/CVE-2026-63623

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