RHSA-2026:18326 - Security Advisory

Topic

An update for libvirt is now available for Red Hat Enterprise Linux 10.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

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 10 Release Notes linked from the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 10 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.2 x86_64
• Red Hat Enterprise Linux for IBM z Systems 10 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.2 s390x
• Red Hat Enterprise Linux for Power, little endian 10 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.2 ppc64le
• Red Hat Enterprise Linux for ARM 64 10 aarch64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.2 aarch64
• Red Hat CodeReady Linux Builder for x86_64 10 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian 10 ppc64le
• Red Hat CodeReady Linux Builder for ARM 64 10 aarch64
• Red Hat CodeReady Linux Builder for IBM z Systems 10 s390x
• Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 10.2 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 10.2 ppc64le
• Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 10.2 s390x
• Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 10.2 aarch64
• Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.2 aarch64
• Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.2 s390x
• Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.2 ppc64le
• Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.2 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 10.2 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 10.2 aarch64
• Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 10.2 ppc64le
• Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 10.2 s390x

Fixes

• BZ - 2413801 - CVE-2025-12748 libvirt: Denial of service in XML parsing
• RHEL-110191 - virtqemud crash while detach disk by virsh cmd detach-device-alias concurrently
• RHEL-72006 - virsh edit can not set "discard_granularity=0" for virtio-blk device
• RHEL-104238 - Rebase libvirt in RHEL-10.2
• RHEL-113574 - Migration fails if qcow2 overlay with data-file is not on shared storage
• RHEL-62032 - Better error message when attaching unsupported controller
• RHEL-7038 - optimize CPU flag probing QMP conversation
• RHEL-79806 - libvirt: Integrate passt --hostname --fqdn options
• RHEL-92842 - passt process is not cleaned when create a user session domain with vhostuser passt
• RHEL-95749 - libvirt need add support for USB CD-ROM drive
• RHEL-87522 - Should reject to config readonly parameter in virtiofs xml for externally launched virtiofsd
• RHEL-95818 - Improve consistency and usability of 'manual' disk snapshot mode
• RHEL-80679 - [RFE] Keep vm/qemu around after guest OS shutdown (if backup job is running)
• RHEL-102925 - The second time migration fails with shared vtpm state
• RHEL-104216 - Can not cross migrate guest with multiple cpu threads [rhel10.2]
• RHEL-104427 - Conflict with earlier configuration for group 'kvm'
• RHEL-118671 - Expose block limits of block nodes
• RHEL-122751 - Virsh can't guest xml from VMware if guest's second disk is in sub-folder
• RHEL-126945 - race condition restoring selinux labels
• RHEL-100716 - libvirt support for loading multiple sets of x509 certificates for PQC hybrid mode
• RHEL-114412 - Get AVC denials when destroy guest with block disk and snapshots
• RHEL-138300 - Can't connect VMware env via ipv6 address by virsh [rhel-10.2]
• RHEL-141820 - virtqemud crashes on the second call dom.setThrottleGroup() [rhel-10]
• RHEL-144089 - virqemud crash when reverting/deleting external snapshots [rhel-10]
• RHEL-145080 - Improve debugging of ESX connection URI lookups
• RHEL-126346 - [RHEL 10.1] libvirt iommufd support for safe device pass-through for TDX
• RHEL-131335 - [RFE] Add libvirt API for block latency histograms [rhel-10]
• RHEL-135115 - Libvirt: Support live migration when persistent reservation are used [rhel-10]
• RHEL-145769 - incremental backup bitmap migration for non-shared qcow2 with data-file contents which are shared
• RHEL-150351 - Add hotplug support for host device with IOMMUFD
• RHEL-82645 - [aarch64] [libvirt] UEFI writable variable service in QEMU
• RHEL-151916 - Virtqemud crash when VFIO hotplug a device

CVEs

• CVE-2025-12748

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/10/html/10.2_release_notes/index