Red Hat Security Advisory: qemu-kvm security update
Kernel-based Virtual Machine (KVM) is a full virtualization solution for Linux on a variety of architectures. The qemu-kvm packages provide the user-space component for running virtual machines that use KVM. Security Fix(es): * qemu-kvm: VNC WebSocket handshake use-after-free (CVE-2025-11234) 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.
AI Analysis
Technical Summary
The qemu-kvm package, which provides the user-space component for running virtual machines using KVM on Red Hat Enterprise Linux 9, contains a use-after-free vulnerability in the VNC WebSocket handshake process (CVE-2025-11234). This vulnerability is classified under CWE-416 (Use After Free). Red Hat has issued a security advisory (RHSA-2026:18772) that includes a patch to fix this issue. The advisory covers multiple architectures supported by Red Hat Enterprise Linux 9 and its Extended Update Support versions. The update is included in the 9.8 release of Red Hat Enterprise Linux 9.
Potential Impact
The vulnerability could potentially allow an attacker to exploit a use-after-free condition during the VNC WebSocket handshake in qemu-kvm, which may lead to undefined behavior such as crashes or memory corruption. Red Hat rates the security impact as moderate. There are no known exploits in the wild at this time.
Mitigation Recommendations
A security update addressing CVE-2025-11234 is available and included in Red Hat Enterprise Linux 9.8. Users should apply the official Red Hat update as described in the advisory RHSA-2026:18772 and the referenced article https://access.redhat.com/articles/11258 to remediate this vulnerability. No additional mitigations are specified by the vendor.
Red Hat Security Advisory: qemu-kvm security update
Description
Kernel-based Virtual Machine (KVM) is a full virtualization solution for Linux on a variety of architectures. The qemu-kvm packages provide the user-space component for running virtual machines that use KVM. Security Fix(es): * qemu-kvm: VNC WebSocket handshake use-after-free (CVE-2025-11234) 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.
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The qemu-kvm package, which provides the user-space component for running virtual machines using KVM on Red Hat Enterprise Linux 9, contains a use-after-free vulnerability in the VNC WebSocket handshake process (CVE-2025-11234). This vulnerability is classified under CWE-416 (Use After Free). Red Hat has issued a security advisory (RHSA-2026:18772) that includes a patch to fix this issue. The advisory covers multiple architectures supported by Red Hat Enterprise Linux 9 and its Extended Update Support versions. The update is included in the 9.8 release of Red Hat Enterprise Linux 9.
Potential Impact
The vulnerability could potentially allow an attacker to exploit a use-after-free condition during the VNC WebSocket handshake in qemu-kvm, which may lead to undefined behavior such as crashes or memory corruption. Red Hat rates the security impact as moderate. There are no known exploits in the wild at this time.
Mitigation Recommendations
A security update addressing CVE-2025-11234 is available and included in Red Hat Enterprise Linux 9.8. Users should apply the official Red Hat update as described in the advisory RHSA-2026:18772 and the referenced article https://access.redhat.com/articles/11258 to remediate this vulnerability. No additional mitigations are specified by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:18772
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- null
Threat ID: 6a535bfb68715ace43ad4e41
Added to database: 07/12/2026, 09:18:51 UTC
Last enriched: 07/12/2026, 09:20:21 UTC
Last updated: 07/16/2026, 22:36:40 UTC
Views: 10
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