CVE-2023-3354

Publication date 11 July 2023

Last updated 9 June 2026

Ubuntu priority

Low

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

Description

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

Package Ubuntu Release Status
qemu 26.04 LTS resolute
Not affected
25.10 questing
Not affected
25.04 plucky
Not affected
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
Fixed 1:2.11+dfsg-1ubuntu7.42+esm5
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

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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

Severity score breakdown

CVSS version: CVSS v3.0

Base score 7.5 · 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)

Other references

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