CVE-2026-34933

Publication date 3 April 2026

Last updated 14 May 2026

Ubuntu priority

Cvss 3 Severity Score

Description

Avahi is a system which facilitates service discovery on a local network via the mDNS/DNS-SD protocol suite. Prior to version 0.9-rc4, any unprivileged local user can crash avahi-daemon by sending a single D-Bus method call with conflicting publish flags. This issue has been patched in version 0.9-rc4.

Status

Show unmaintained releases

Package	Ubuntu Release	Status
avahi	26.04 LTS resolute	Fixed 0.8-18ubuntu1.1
	25.10 questing	Fixed 0.8-16ubuntu3.2
	24.04 LTS noble	Fixed 0.8-13ubuntu6.2
	22.04 LTS jammy	Fixed 0.8-5ubuntu5.5
	20.04 LTS focal	Fixed 0.7-4ubuntu7.3+esm2
	18.04 LTS bionic	Fixed 0.7-3.1ubuntu1.3+esm4
	16.04 LTS xenial	Fixed 0.6.32~rc+dfsg-1ubuntu2.3+esm5
	14.04 LTS trusty	Fixed 0.6.31-4ubuntu1.3+esm5

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Patch details

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

Package	Patch details
avahi	Upstream: 0be89b6 Upstream: a93fdd9

Severity score breakdown

Parameter	Value
Base score	5.5 · Medium
Attack vector	Local
Attack complexity	Low
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality	None
Integrity impact	None
Availability impact	High
Vector	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

USN-8269-1
Avahi vulnerabilities
12 May 2026