Ubuntu 20.04 LTS / 22.04 LTS / 23.04 / 23.10 : QEMU vulnerabilities (USN-6567-1)

high Nessus Plugin ID 187683


The remote Ubuntu host is missing one or more security updates.


The remote Ubuntu 20.04 LTS / 22.04 LTS / 23.04 / 23.10 host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-6567-1 advisory.

- An infinite loop flaw was found in the USB xHCI controller emulation of QEMU while computing the length of the Transfer Request Block (TRB) Ring. This flaw allows a privileged guest user to hang the QEMU process on the host, resulting in a denial of service. (CVE-2020-14394)

- An issue was discovered in TCG Accelerator in QEMU 4.2.0, allows local attackers to execute arbitrary code, escalate privileges, and cause a denial of service (DoS). (CVE-2020-24165)

- A stack overflow vulnerability was found in the Intel HD Audio device (intel-hda) of QEMU. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service condition. The highest threat from this vulnerability is to system availability. This flaw affects QEMU versions prior to 7.0.0. (CVE-2021-3611)

- An out-of-bounds memory access flaw was found in the ATI VGA device emulation of QEMU. This flaw occurs in the ati_2d_blt() routine while handling MMIO write operations when the guest provides invalid values for the destination display parameters. A malicious guest could use this flaw to crash the QEMU process on the host, resulting in a denial of service. (CVE-2021-3638)

- A flaw was found in the QEMU implementation of VMWare's paravirtual RDMA device. This flaw allows a crafted guest driver to allocate and initialize a huge number of page tables to be used as a ring of descriptors for CQ and async events, potentially leading to an out-of-bounds read and crash of QEMU.

- A flaw was found in the 9p passthrough filesystem (9pfs) implementation in QEMU. The 9pfs server did not prohibit opening special files on the host side, potentially allowing a malicious client to escape from the exported 9p tree by creating and opening a device file in the shared folder. (CVE-2023-2861)

- A flaw was found in the QEMU virtual crypto device while handling data encryption/decryption requests in virtio_crypto_handle_sym_req. There is no check for the value of `src_len` and `dst_len` in virtio_crypto_sym_op_helper, potentially leading to a heap buffer overflow when the two values differ.

- A flaw was found in the QEMU built-in VNC server while processing ClientCutText messages. A wrong exit condition may lead to an infinite loop when inflating an attacker controlled zlib buffer in the `inflate_buffer` function. This could allow a remote authenticated client who is able to send a clipboard to the VNC server to trigger a denial of service. (CVE-2023-3255)

- A flaw was found in QEMU. The async nature of hot-unplug enables a race scenario where the net device backend is cleared before the virtio-net pci frontend has been unplugged. A malicious guest could use this time window to trigger an assertion and cause a denial of service. (CVE-2023-3301)

- A flaw was found in the QEMU built-in VNC server. When a client connects to the VNC server, QEMU checks whether the current number of connections crosses a certain threshold and if so, cleans up the previous connection. If the previous connection happens to be in the handshake phase and fails, QEMU cleans up the connection again, resulting in a NULL pointer dereference issue. This could allow a remote unauthenticated client to cause a denial of service. (CVE-2023-3354)

- QEMU through 8.0.4 accesses a NULL pointer in nvme_directive_receive in hw/nvme/ctrl.c because there is no check for whether an endurance group is configured before checking whether Flexible Data Placement is enabled. (CVE-2023-40360)

- A heap out-of-bounds memory read flaw was found in the virtual nvme device in QEMU. The QEMU process does not validate an offset provided by the guest before computing a host heap pointer, which is used for copying data back to the guest. Arbitrary heap memory relative to an allocated buffer can be disclosed.

- QEMU through 8.0.0 could trigger a division by zero in scsi_disk_reset in hw/scsi/scsi-disk.c because scsi_disk_emulate_mode_select does not prevent s->qdev.blocksize from being 256. This stops QEMU and the guest immediately. (CVE-2023-42467)

- A bug in QEMU could cause a guest I/O operation otherwise addressed to an arbitrary disk offset to be targeted to offset 0 instead (potentially overwriting the VM's boot code). This could be used, for example, by L2 guests with a virtual disk (vdiskL2) stored on a virtual disk of an L1 (vdiskL1) hypervisor to read and/or write data to LBA 0 of vdiskL1, potentially gaining control of L1 at its next reboot.

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


Update the affected packages.

See Also


Plugin Details

Severity: High

ID: 187683

File Name: ubuntu_USN-6567-1.nasl

Version: 1.3

Type: local

Agent: unix

Published: 1/8/2024

Updated: 3/15/2024

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information


Risk Factor: High

Score: 7.4


Risk Factor: Low

Base Score: 2.1

Temporal Score: 1.6

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

CVSS Score Source: CVE-2021-3638


Risk Factor: High

Base Score: 8.8

Temporal Score: 7.9

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

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

CVSS Score Source: CVE-2020-24165

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:20.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:qemu-system-common, p-cpe:/a:canonical:ubuntu_linux:qemu-user, p-cpe:/a:canonical:ubuntu_linux:qemu-guest-agent, p-cpe:/a:canonical:ubuntu_linux:qemu-system-gui, p-cpe:/a:canonical:ubuntu_linux:qemu-system-xen, p-cpe:/a:canonical:ubuntu_linux:qemu-system, p-cpe:/a:canonical:ubuntu_linux:qemu-user-static, p-cpe:/a:canonical:ubuntu_linux:qemu-kvm, p-cpe:/a:canonical:ubuntu_linux:qemu-system-mips, p-cpe:/a:canonical:ubuntu_linux:qemu, p-cpe:/a:canonical:ubuntu_linux:qemu-system-x86-xen, p-cpe:/a:canonical:ubuntu_linux:qemu-system-s390x, p-cpe:/a:canonical:ubuntu_linux:qemu-system-x86, p-cpe:/a:canonical:ubuntu_linux:qemu-system-misc, p-cpe:/a:canonical:ubuntu_linux:qemu-system-arm, p-cpe:/a:canonical:ubuntu_linux:qemu-system-x86-microvm, cpe:/o:canonical:ubuntu_linux:23.10, p-cpe:/a:canonical:ubuntu_linux:qemu-utils, p-cpe:/a:canonical:ubuntu_linux:qemu-system-ppc, p-cpe:/a:canonical:ubuntu_linux:qemu-user-binfmt, cpe:/o:canonical:ubuntu_linux:23.04, cpe:/o:canonical:ubuntu_linux:22.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:qemu-system-data, p-cpe:/a:canonical:ubuntu_linux:qemu-block-extra, p-cpe:/a:canonical:ubuntu_linux:qemu-system-sparc

Required KB Items: Host/cpu, Host/Debian/dpkg-l, Host/Ubuntu, Host/Ubuntu/release

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 1/8/2024

Vulnerability Publication Date: 3/3/2022

Reference Information

CVE: CVE-2020-14394, CVE-2020-24165, CVE-2021-3611, CVE-2021-3638, CVE-2023-1544, CVE-2023-2861, CVE-2023-3180, CVE-2023-3255, CVE-2023-3301, CVE-2023-3354, CVE-2023-40360, CVE-2023-4135, CVE-2023-42467, CVE-2023-5088

IAVB: 2023-B-0058-S, 2023-B-0073-S, 2024-B-0022

USN: 6567-1