# CVE-2025-12748: Libvirt: denial of service in xml parsing

Status: published. Published: 2025-11-11. Updated: 2026-11-05.

A flaw was discovered in libvirt in the XML file processing. More specifically, the parsing of user provided XML files was performed before the ACL checks. A malicious user with limited permissions could exploit this flaw by submitting a specially crafted XML file, causing libvirt to allocate too much memory on the host. The excessive memory consumption could lead to a libvirt process crash on the host, resulting in a denial-of-service condition.

## 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

-  /  (libvirt): ≥ 0; ≤ 11.9.0 (affected, semver). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10 (libvirt): ≥ 0:11.10.0-12.el10_2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libvirt): ≥ 0:11.10.0-12.el9_8; < * (unaffected, rpm). 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

## Severity and prioritization

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

- CISA KEV: No listing in collected sources

- EPSS: 0.22% as of 2026-11-05; percentile 13.07%

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

- Weaknesses: CWE-770

## Exploit evidence

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

## References

- https://access.redhat.com/errata/RHSA-2026:18326 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:18748 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2025-12748 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2413801 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2025-12748; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2025-12748; retrieved 2026-11-05; source updated Not reported

Revision: d14955c82732b3df4148fc8e4a1cb0f43bc750f141a91a096d4ecba426511e15

Canonical: https://y2.dev/cve/CVE-2025-12748

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