RHEL 9 : libvirt (RHSA-2026:18748)

medium Nessus Plugin ID 315414

Synopsis

The remote Red Hat host is missing a security update for libvirt.

Description

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:18748 advisory.

Kernel-based Virtual Machine (KVM) offers a full virtualization solution forLinux on numerous hardware platforms. The virt:rhel module contains packageswhich provide user-space components used to run virtual machines using KVM.The packages also provide APIs for managing and interacting with the virtualized systems.

Security Fix(es):

* libvirt: Denial of service in XML parsing (CVE-2025-12748)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Red Hat Enterprise Linux 9 Release Notes linked from the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the RHEL libvirt package based on the guidance in RHSA-2026:18748.

See Also

http://www.nessus.org/u?77b8d12b

https://access.redhat.com/security/updates/classification/#moderate

https://bugzilla.redhat.com/show_bug.cgi?id=2413801

https://issues.redhat.com/browse/RHEL-108915

https://issues.redhat.com/browse/RHEL-114003

https://issues.redhat.com/browse/RHEL-116847

https://issues.redhat.com/browse/RHEL-118197

https://issues.redhat.com/browse/RHEL-126345

https://issues.redhat.com/browse/RHEL-134127

https://issues.redhat.com/browse/RHEL-135128

https://issues.redhat.com/browse/RHEL-138689

https://issues.redhat.com/browse/RHEL-141496

https://issues.redhat.com/browse/RHEL-146629

http://www.nessus.org/u?2c352143

https://access.redhat.com/errata/RHSA-2026:18748

Plugin Details

Severity: Medium

ID: 315414

File Name: redhat-RHSA-2026-18748.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 5/19/2026

Updated: 5/19/2026

Supported Sensors: Continuous Assessment, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

Vendor

Vendor Severity: Moderate

CVSS v2

Risk Factor: Medium

Base Score: 4.6

Temporal Score: 3.4

Vector: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C

CVSS Score Source: CVE-2025-12748

CVSS v3

Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-proxy, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon, p-cpe:/a:redhat:enterprise_linux:libvirt-client, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-rbd, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-iscsi, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-lock, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-plugin-sanlock, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-core, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-logical, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-scsi, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-log, p-cpe:/a:redhat:enterprise_linux:libvirt-nss, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-config-network, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-config-nwfilter, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-secret, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-nodedev, p-cpe:/a:redhat:enterprise_linux:libvirt, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-network, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-common, p-cpe:/a:redhat:enterprise_linux:libvirt-client-qemu, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-nwfilter, p-cpe:/a:redhat:enterprise_linux:libvirt-libs, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-qemu, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-disk, p-cpe:/a:redhat:enterprise_linux:libvirt-devel, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-interface, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-plugin-lockd, p-cpe:/a:redhat:enterprise_linux:libvirt-docs, p-cpe:/a:redhat:enterprise_linux:libvirt-ssh-proxy, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-kvm, p-cpe:/a:redhat:enterprise_linux:libvirt-daemon-driver-storage-mpath

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu

Exploit Ease: No known exploits are available

Patch Publication Date: 5/19/2026

Vulnerability Publication Date: 11/11/2025

Reference Information

CVE: CVE-2025-12748

CWE: 770

RHSA: 2026:18748