CVE-2023-3354

Publication date 11 July 2023

Last updated 24 July 2024

Ubuntu priority

Cvss 3 Severity Score

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.

Read the notes from the security team

Why is this CVE low priority?

Limited to a denial of service in the VNC server component.

Learn more about Ubuntu priority

Status

Show unmaintained releases

Package	Ubuntu Release	Status
qemu	24.10 oracular	Not affected
	24.04 LTS noble	Not affected
	23.10 mantic	Not affected
	23.04 lunar	Fixed 1:7.2+dfsg-5ubuntu2.4
	22.10 kinetic	Ignored end of life, was deferred [2023-07-04]
	22.04 LTS jammy	Fixed 1:6.2+dfsg-2ubuntu6.16
	20.04 LTS focal	Fixed 1:4.2-3ubuntu6.28
	18.04 LTS bionic	Vulnerable
	16.04 LTS xenial	Vulnerable
	14.04 LTS trusty	Vulnerable

Notes

mdeslaur

VNC denial of service

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package	Patch details
qemu	Upstream: 10be627

Severity score breakdown

Parameter	Value
Base score	7.5 · High
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-6567-1
QEMU vulnerabilities
8 January 2024