An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to trigger out-of-bounds heap accesses in the QEMU process via the emulated Xen physdev hypercall interface, leading to a denial of service or potential memory corruption.

Security Update for QEMU

The remote Oracle Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2026-50241 advisory.

    - Document CVEs (Mark Kanda) {CVE-2025-54566} {CVE-2025-54567} {CVE-2025-8860} {CVE-2026-0665}     {CVE-2026-3886}
    - hw/usb/hcd-ohci: check for MPS=0 to avoid infinite loop (Jenny Guanni Qu) [Orabug: 39160764]     {CVE-2026-3890}
    - hyperv/syndbg: check length returned by cpu_physical_memory_map() (Paolo Bonzini) [Orabug: 39160749]     {CVE-2026-3842}
    - block/vmdk: fix OOB read in vmdk_read_extent() (Halil Oktay) [Orabug: 39160776] {CVE-2026-2243}
    - cryptodev-builtin: Limit the maximum size (zhenwei pi) [Orabug: 39173335] {CVE-2025-14876}
    - hw/virtio/virtio-crypto: verify asym request size (zhenwei pi) [Orabug: 39173335] {CVE-2025-14876}
    - io: fix use after free in websocket handshake code (Daniel P. Berrange) [Orabug: 38687831]     {CVE-2025-11234}
    - hw/usb/hcd-uhci: don't assert for SETUP to non-0 endpoint (Peter Maydell) [Orabug: 37517799]     {CVE-2024-8354}

Tenable has extracted the preceding description block directly from the Oracle Linux 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 Oracle Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2026-50239 advisory.

    - Limit recursion in ri-records (CVE-2021-3622)       resolves: rhbz#1976194
    - Bounds check for block exceeding page length (CVE-2021-3504)       resolves: rhbz#1950501
    - Fixes: CVE-2022-40284
    - Fixes: CVE-2021-46790, CVE-2022-30783, CVE-2022-30784, CVE-2022-30785,       CVE-2022-30786, CVE-2022-30787, CVE-2022-30788, CVE-2022-30789       resolves: rhbz#2127240 rhbz#2127248       (also: 2127233 2127234 2127241 2127249 2127255 2127256 2127262 2127263)
    - Fixes: CVE-2021-33285, CVE-2021-33286, CVE-2021-33287, CVE-2021-33289,       CVE-2021-35266, CVE-2021-35267, CVE-2021-35268, CVE-2021-35269,       CVE-2021-39251, CVE-2021-39252, CVE-2021-39253, CVE-2021-39254       resolves: rhbz#2004490
    - Fix for CVE-2019-9755       (heap-based buffer overflow leads to local root privilege escalation)       resolves: rhbz#1698503
    - Fix CVE-2024-7383 NBD server improper certificate validation       resolves: RHEL-52728
    - Fix CVE-2022-0485: Fail nbdcopy if NBD read or write fails       resolves: rhbz#2045718
    - Contains fix for NBD Protocol Downgrade Attack (CVE-2019-14842).
    - Fix CVE-2025-49133       Resolves: RHEL-96251
    - Backport 'tpm2: Check size of buffer before accessing it' (CVE-2023-1017 & CVE-2023-1018)       Resolves: rhbz#2173964       Resolves: rhbz#2173970
    - Fix CVE-2021-3746 libtpms: out-of-bounds access via specially crafted TPM 2 command packets       Resolves: rhbz#1999307
    - Fix CVE-2021-3623: out-of-bounds access when trying to resume the state of the vTPM       Fixes: rhbz#1976816
    - Fix CVE-2021-3716 NBD_OPT_STRUCTURED_REPLY injection on STARTTLS       resolves: rhbz#1994915
    - Document CVEs (Mark Kanda) {CVE-2025-54566} {CVE-2025-54567} {CVE-2025-8860} {CVE-2026-0665}     {CVE-2026-3886}
    - hw/usb/hcd-ohci: check for MPS=0 to avoid infinite loop (Jenny Guanni Qu) [Orabug: 39160764]     {CVE-2026-3890}
    - hyperv/syndbg: check length returned by cpu_physical_memory_map() (Paolo Bonzini) [Orabug: 39160749]     {CVE-2026-3842}
    - block/vmdk: fix OOB read in vmdk_read_extent() (Halil Oktay) [Orabug: 39160776] {CVE-2026-2243}
    - cryptodev-builtin: Limit the maximum size (zhenwei pi) [Orabug: 39173335] {CVE-2025-14876}
    - hw/virtio/virtio-crypto: verify asym request size (zhenwei pi) [Orabug: 39173335] {CVE-2025-14876}
    - io: fix use after free in websocket handshake code (Daniel P. Berrange) [Orabug: 38687831]     {CVE-2025-11234}
    - hw/usb/hcd-uhci: don't assert for SETUP to non-0 endpoint (Peter Maydell) [Orabug: 37517799]     {CVE-2024-8354}
    - Add fix for CVE-2022-23645.
      Resolves: rhbz#2056517
    - Update to 0.4.2, to address potential symlink vulnerabilities (CVE-2020-28407).
      Resolves: rhbz#1906043
    - Fix CVE-2022-2211 Denial of Service in --key parameter       resolves: rhbz#2102720

Tenable has extracted the preceding description block directly from the Oracle Linux 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-2026:20357-1 advisory.

    - Update to version 10.0.8
    - CVE-2025-14876: Fixed unbounded allocation in virtio-crypto. (bsc#1255400)
    - CVE-2026-0665: Fixed PIRQ bounds check in xen_physdev_map_pirq. (bsc#1256484)

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 Ubuntu 22.04 LTS / 24.04 LTS / 25.10 host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8073-1 advisory.

    It was discovered that the UHCI controller implementation of QEMU could be brought into an invalid state.
    An attacker inside the guest could possibly use this issue to cause QEMU to crash, resulting in a denial     of service. (CVE-2024-8354)

    It was discovered that QEMU incorrectly handled memory during certain VNC operations. An remote attacker     could possibly use this issue to cause QEMU to crash, resulting in a denial of service, or possibly     execute arbitrary code. (CVE-2025-11234)

    It was discovered that the e1000 network device implementation of QEMU could be made to write out of     bounds. An attacker inside the guest could possibly use this issue to cause QEMU to crash, resulting in a     denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 24.04 LTS and     Ubuntu 25.10. (CVE-2025-12464)

    It was discovered that the virtio-crypto device implementation of QEMU did not limit the length of a     certain path input. An attacker inside the guest could possibly use this issue to cause QEMU to consume     large amount of memory, resulting in a denial of service. This issue only affected Ubuntu 24.04 LTS and     Ubuntu 25.10. (CVE-2025-14876)

    It was discovered that the KVM Xen guest support of QEMU could be made to read out of bounds. An attacker     inside the guest could possibly use this issue to cause QEMU to crash, resulting in a denial of service.
    This issue only affected Ubuntu 24.04 LTS and Ubuntu 25.10. (CVE-2026-0665)

Tenable has extracted the preceding description block directly from the Ubuntu 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 15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:0662-1 advisory.

    - CVE-2025-14876: qemu-kvm: Unbounded allocation in virtio-crypto (bsc#1255400).
    - CVE-2026-0665: out-of-bounds heap access can lead to a denial of service or potential memory corruption     (bsc#1256484).

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 version of Tencent Linux installed on the remote TencentOS Server 4 host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the TSSA-2026:0097 advisory.

    Package updates are available for TencentOS Server 4 that fix the following vulnerabilities:

    CVE-2026-0665:
    qemu-kvm: Heap off-by-one in KVM Xen PHYSDEVOP_map_pirq

Tenable has extracted the preceding description block directly from the Tencent 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 a vulnerability as referenced in the SUSE-SU-2026:0445-1 advisory.

    - CVE-2026-0665: Added PIRQ bounds check in xen_physdev_map_pirq to avoid an out-of-bounds heap.
    (bsc#1256484)

    Other fixes:

    - Fixed that QEMU migration fails if a qemu-vdagent channel is present in the VM (bsc#1257474)

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

  - An off-by-one error was found in QEMU's KVM Xen guest support. A malicious guest could use this flaw to     trigger out-of-bounds heap accesses in the QEMU process via the emulated Xen physdev hypercall interface,     leading to a denial of service or potential memory corruption. (CVE-2026-0665)

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

ID	Name	Product	Family	Severity
310733	Oracle Linux 9 : qemu-kvm (ELSA-2026-50241)	Nessus	Oracle Linux Local Security Checks	medium
310544	Oracle Linux 8 : virt:kvm_utils3 (ELSA-2026-50239)	Nessus	Oracle Linux Local Security Checks	medium
302343	openSUSE 16 Security Update : qemu (openSUSE-SU-2026:20357-1)	Nessus	SuSE Local Security Checks	medium
301155	Ubuntu 22.04 LTS / 24.04 LTS / 25.10 : QEMU vulnerabilities (USN-8073-1)	Nessus	Ubuntu Local Security Checks	medium
300522	openSUSE 15 Security Update : qemu (SUSE-SU-2026:0662-1)	Nessus	SuSE Local Security Checks	medium
300283	TencentOS Server 4: qemu (TSSA-2026:0097)	Nessus	Tencent Local Security Checks	medium
298729	SUSE SLED15 / SLES15 Security Update : qemu (SUSE-SU-2026:0445-1)	Nessus	SuSE Local Security Checks	medium
282642	Linux Distros Unpatched Vulnerability : CVE-2026-0665	Nessus	Misc.	medium

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