A flaw was found in QEMU. If the QIOChannelWebsock object is freed while it is waiting to complete a handshake, a GSource is leaked. This can lead to the callback firing later on and triggering a use-after-free in the use of the channel. This can be abused by a malicious client with network access to the VNC WebSocket port to cause a denial of service during the WebSocket handshake prior to the VNC client authentication.

The remote SUSE Linux SLES15 / SLES_SAP15 host has packages installed that are affected by a vulnerability as referenced in the SUSE-SU-2026:0436-1 advisory.

    - CVE-2025-11234: Fixed use-after-free in websocket handshake code can lead to denial of service     (bsc#1250984).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

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

The remote AlmaLinux 10 host has packages installed that are affected by a vulnerability as referenced in the ALSA-2026:1831 advisory.

    * qemu-kvm: VNC WebSocket handshake use-after-free (CVE-2025-11234)

Tenable has extracted the preceding description block directly from the AlmaLinux security advisory.

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

The remote RockyLinux 10 host has packages installed that are affected by a vulnerability as referenced in the RLSA-2026:1831 advisory.

    * qemu-kvm: VNC WebSocket handshake use-after-free (CVE-2025-11234)

Tenable has extracted the preceding description block directly from the RockyLinux security advisory.

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

The remote Redhat Enterprise Linux 10 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:1831 advisory.

    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.

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.

The remote Oracle Linux 10 host has packages installed that are affected by a vulnerability as referenced in the ELSA-2026-1831 advisory.

    - Resolves: RHEL-120118       (CVE-2025-11234 qemu-kvm: VNC WebSocket handshake use-after-free [rhel-10.1.z])

Tenable has extracted the preceding description block directly from the Oracle 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.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:0288-1 advisory.

    Security issues fixed:

    - CVE-2025-12464: stack-based buffer overflow in the e1000 network device operations can be exploited by a     malicious       guest user to crash the QEMU process on the host (bsc#1253002).
    - CVE-2025-11234: use-after-free in WebSocket handshake operations can be exploited by a malicious client     with network       access to the VNC WebSocket port to cause a denial-of-service (bsc#1250984).

    Other updates and bugfixes:

    - [openSUSE][RPM] spec: require qemu-hw-display-virtio-gpu-pci for x86 too.
    - [openSUSE][RPM] spec: make glusterfs support conditional (bsc#1254494).
    - [openSUSE][RPM]: really fix *-virtio-gpu-pci dependency on ARM (bsc#1254286).
    - block/curl: fix curl internal handles handling (bsc#1252768).
    - [openSUSE][RPM] spec: qemu-vgabios is required on ppc (bsc#1230042).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

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

The remote SUSE Linux SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:0039-1 advisory.

    - CVE-2024-6505: qemu-kvm: virtio-net: Fixed queue index       out-of-bounds access in software RSS (bsc#1227397)
    - CVE-2025-12464: net: pad packets to minimum length in       qemu_receive_packet() (bsc#1253002)
    - CVE-2025-11234: qemu-kvm: Fixed use-after-free in websocket       handshake code leading to denial of service (bsc#1250984)

    Other fixes:
    - Fixed *-virtio-gpu-pci dependency on ARM (bsc#1254286)
    - block/curl: Fixed curl internal handles handling (bsc#1252768)

Tenable has extracted the preceding description block directly from the SUSE security advisory.

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

The remote SUSE Linux SLES15 / SLES_SAP15 / openSUSE 15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:0022-1 advisory.

    Security issues fixed:

    - CVE-2025-12464: stack-based buffer overflow in the e1000 network device operations can be exploited by a     malicious       guest user to crash the QEMU process on the host (bsc#1253002).
    - CVE-2025-11234: use-after-free in WebSocket handshake operations can be exploited by a malicious client     with network       access to the VNC WebSocket port to cause a denial-of-service (bsc#1250984).

    Other updates and bugfixes:

    - [openSUSE][RPM]: really fix *-virtio-gpu-pci dependency on ARM (bsc#1254286).
    - block/curl: fix curl internal handles handling (bsc#1252768).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

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

The remote SUSE Linux SLES16 / SLES_SAP16 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2025:21233-1 advisory.

    Update to version 10.0.7.

    Security issues fixed:

    - CVE-2025-12464: stack-based buffer overflow in the e1000 network device operations can be exploited by a     malicious       guest user to crash the QEMU process on the host (bsc#1253002).
    - CVE-2025-11234: use-after-free in WebSocket handshake operations can be exploited by a malicious client     with network       access to the VNC WebSocket port to cause a denial-of-service (bsc#1250984).

    Other updates and bugfixes:

    - Version 10.0.7:
      * kvm: Fix kvm_vm_ioctl() and kvm_device_ioctl() return value
      * docs/devel: Update URL for make-pullreq script
      * target/arm: Fix assert on BRA.
      * hw/aspeed/{xdma, rtc, sdhci}: Fix endianness to DEVICE_LITTLE_ENDIAN
      * hw/core/machine: Provide a description for aux-ram-share property
      * hw/pci: Make msix_init take a uint32_t for nentries
      * block/io_uring: avoid potentially getting stuck after resubmit at the end of ioq_submit()
      * block-backend: Fix race when resuming queued requests
      * ui/vnc: Fix qemu abort when query vnc info
      * chardev/char-pty: Do not ignore chr_write() failures
      * hw/display/exynos4210_fimd: Account for zero length in fimd_update_memory_section()
      * hw/arm/armv7m: Disable reentrancy guard for v7m_sysreg_ns_ops MRs
      * hw/arm/aspeed: Fix missing SPI IRQ connection causing DMA interrupt failure
      * migration: Fix transition to COLO state from precopy
      * Full backport list: https://lore.kernel.org/qemu-     devel/1765037524.347582.2700543.nullmailer@tls.msk.ru/

    - Version 10.0.6:
      * linux-user/microblaze: Fix little-endianness binary
      * target/hppa: correct size bit parity for fmpyadd
      * target/i386: user: do not set up a valid LDT on reset
      * async: access bottom half flags with qatomic_read
      * target/i386: fix x86_64 pushw op
      * i386/tcg/smm_helper: Properly apply DR values on SMM entry / exit
      * i386/cpu: Prevent delivering SIPI during SMM in TCG mode
      * i386/kvm: Expose ARCH_CAP_FB_CLEAR when invulnerable to MDS
      * target/i386: Fix CR2 handling for non-canonical addresses
      * block/curl.c: Use explicit long constants in curl_easy_setopt calls
      * pcie_sriov: Fix broken MMIO accesses from SR-IOV VFs
      * target/riscv: rvv: Fix vslide1[up|down].vx unexpected result when XLEN2 and SEWd
      * target/riscv: Fix ssamoswap error handling
      * Full backport list: https://lore.kernel.org/qemu-devel/1761022287.744330.6357.nullmailer@tls.msk.ru/

    - Version 10.0.5:
      * tests/functional/test_aarch64_sbsaref_freebsd: Fix the URL of the ISO image
      * tests/functional/test_ppc_bamboo: Replace broken link with working assets
      * physmem: Destroy all CPU AddressSpaces on unrealize
      * memory: New AS helper to serialize destroy+free
      * include/system/memory.h: Clarify address_space_destroy() behaviour
      * migration: Fix state transition in postcopy_start() error handling
      * target/riscv: rvv: Modify minimum VLEN according to enabled vector extensions
      * target/riscv: rvv: Replace checking V by checking Zve32x
      * target/riscv: Fix endianness swap on compressed instructions
      * hw/riscv/riscv-iommu: Fixup PDT Nested Walk
      * Full backport list: https://lore.kernel.org/qemu-devel/1759986125.676506.643525.nullmailer@tls.msk.ru/

    - [openSUSE][RPM]: really fix *-virtio-gpu-pci dependency on ARM (bsc#1254286).
    - [openSUSE][RPM] spec: make glusterfs support conditional (bsc#1254494).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

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

The remote openSUSE 16 host has packages installed that are affected by multiple vulnerabilities as referenced in the openSUSE-SU-2025:20171-1 advisory.

    Update to version 10.0.7.

    Security issues fixed:

    - CVE-2025-12464: stack-based buffer overflow in the e1000 network device operations can be exploited by a     malicious       guest user to crash the QEMU process on the host (bsc#1253002).
    - CVE-2025-11234: use-after-free in WebSocket handshake operations can be exploited by a malicious client     with network       access to the VNC WebSocket port to cause a denial-of-service (bsc#1250984).

    Other updates and bugfixes:

    - Version 10.0.7:
      * kvm: Fix kvm_vm_ioctl() and kvm_device_ioctl() return value
      * docs/devel: Update URL for make-pullreq script
      * target/arm: Fix assert on BRA.
      * hw/aspeed/{xdma, rtc, sdhci}: Fix endianness to DEVICE_LITTLE_ENDIAN
      * hw/core/machine: Provide a description for aux-ram-share property
      * hw/pci: Make msix_init take a uint32_t for nentries
      * block/io_uring: avoid potentially getting stuck after resubmit at the end of ioq_submit()
      * block-backend: Fix race when resuming queued requests
      * ui/vnc: Fix qemu abort when query vnc info
      * chardev/char-pty: Do not ignore chr_write() failures
      * hw/display/exynos4210_fimd: Account for zero length in fimd_update_memory_section()
      * hw/arm/armv7m: Disable reentrancy guard for v7m_sysreg_ns_ops MRs
      * hw/arm/aspeed: Fix missing SPI IRQ connection causing DMA interrupt failure
      * migration: Fix transition to COLO state from precopy
      * Full backport list: https://lore.kernel.org/qemu-     devel/1765037524.347582.2700543.nullmailer@tls.msk.ru/

    - Version 10.0.6:
      * linux-user/microblaze: Fix little-endianness binary
      * target/hppa: correct size bit parity for fmpyadd
      * target/i386: user: do not set up a valid LDT on reset
      * async: access bottom half flags with qatomic_read
      * target/i386: fix x86_64 pushw op
      * i386/tcg/smm_helper: Properly apply DR values on SMM entry / exit
      * i386/cpu: Prevent delivering SIPI during SMM in TCG mode
      * i386/kvm: Expose ARCH_CAP_FB_CLEAR when invulnerable to MDS
      * target/i386: Fix CR2 handling for non-canonical addresses
      * block/curl.c: Use explicit long constants in curl_easy_setopt calls
      * pcie_sriov: Fix broken MMIO accesses from SR-IOV VFs
      * target/riscv: rvv: Fix vslide1[up|down].vx unexpected result when XLEN2 and SEWd
      * target/riscv: Fix ssamoswap error handling
      * Full backport list: https://lore.kernel.org/qemu-devel/1761022287.744330.6357.nullmailer@tls.msk.ru/

    - Version 10.0.5:
      * tests/functional/test_aarch64_sbsaref_freebsd: Fix the URL of the ISO image
      * tests/functional/test_ppc_bamboo: Replace broken link with working assets
      * physmem: Destroy all CPU AddressSpaces on unrealize
      * memory: New AS helper to serialize destroy+free
      * include/system/memory.h: Clarify address_space_destroy() behaviour
      * migration: Fix state transition in postcopy_start() error handling
      * target/riscv: rvv: Modify minimum VLEN according to enabled vector extensions
      * target/riscv: rvv: Replace checking V by checking Zve32x
      * target/riscv: Fix endianness swap on compressed instructions
      * hw/riscv/riscv-iommu: Fixup PDT Nested Walk
      * Full backport list: https://lore.kernel.org/qemu-devel/1759986125.676506.643525.nullmailer@tls.msk.ru/

    - [openSUSE][RPM]: really fix *-virtio-gpu-pci dependency on ARM (bsc#1254286).
    - [openSUSE][RPM] spec: make glusterfs support conditional (bsc#1254494).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

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

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2025:23228 advisory.

    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.

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.

The version of qemu installed on the remote host is prior to 3.1.0-8. It is, therefore, affected by a vulnerability as referenced in the ALAS2-2025-3044 advisory.

    A flaw was found in QEMU. If the QIOChannelWebsock object is freed while it is waiting to complete a     handshake, a GSource is leaked. This can lead to the callback firing later on and triggering a use-after-     free in the use of the channel. This can be abused by a malicious client with network access to the VNC     WebSocket port to cause a denial of service during the WebSocket handshake prior to the VNC client     authentication. (CVE-2025-11234)

Tenable has extracted the preceding description block directly from the tested product security advisory.

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

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - A flaw was found in QEMU. If the QIOChannelWebsock object is freed while it is waiting to complete a     handshake, a GSource is leaked. This can lead to the callback firing later on and triggering a use-after-     free in the use of the channel. This can be abused by a malicious client with network access to the VNC     WebSocket port to cause a denial of service during the WebSocket handshake prior to the VNC client     authentication. (CVE-2025-11234)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Severity
298727	SUSE SLES15 Security Update : qemu (SUSE-SU-2026:0436-1)	Nessus	SuSE Local Security Checks	high
298507	AlmaLinux 10 : qemu-kvm (ALSA-2026:1831)	Nessus	Alma Linux Local Security Checks	high
298206	RockyLinux 10 : qemu-kvm (RLSA-2026:1831)	Nessus	Rocky Linux Local Security Checks	high
298157	RHEL 10 : qemu-kvm (RHSA-2026:1831)	Nessus	Red Hat Local Security Checks	high
297860	Oracle Linux 10 : qemu-kvm (ELSA-2026-1831)	Nessus	Oracle Linux Local Security Checks	high
296664	SUSE SLED15 / SLES15 Security Update : qemu (SUSE-SU-2026:0288-1)	Nessus	SuSE Local Security Checks	high
281910	SUSE SLES15 Security Update : qemu (SUSE-SU-2026:0039-1)	Nessus	SuSE Local Security Checks	medium
281891	SUSE SLES15 / openSUSE 15 Security Update : qemu (SUSE-SU-2026:0022-1)	Nessus	SuSE Local Security Checks	high
279669	SUSE SLES16 Security Update : qemu (SUSE-SU-2025:21233-1)	Nessus	SuSE Local Security Checks	high
279668	openSUSE 16 Security Update : qemu (openSUSE-SU-2025:20171-1)	Nessus	SuSE Local Security Checks	high
278988	RHEL 9 : qemu-kvm (RHSA-2025:23228)	Nessus	Red Hat Local Security Checks	high
271772	Amazon Linux 2 : qemu, --advisory ALAS2-2025-3044 (ALAS-2025-3044)	Nessus	Amazon Linux Local Security Checks	high
269461	Linux Distros Unpatched Vulnerability : CVE-2025-11234	Nessus	Misc.	high

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CVE-2025-11234

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