Postfix Denial of Service Vulnerability in Ubuntu Releases

Postfix Denial of Service Vulnerability in Ubuntu Releases

First seen 7 May 2026, 21:08 UTC UbuntuLinuxsecuritylaunchpad.net 89% similarity 45.9

Article Content

Browse articles
ThreatCluster

A denial of service vulnerability has been identified in Postfix, affecting multiple Ubuntu releases including 26.04 LTS, 25.10, 24.04 LTS, and 22.04 LTS. Discovered by Kamil Frankowicz, the flaw allows remote attackers to crash Postfix by sending specially crafted network traffic. The vulnerability is tracked as CVE-2026-43964, which was published on May 4, 2026. Users are advised to update their systems to the latest package versions to mitigate the risk. The affected versions include Postfix 3.10.6-4ubuntu2.1 for Ubuntu 26.04 LTS and earlier versions for other releases. A standard system update is recommended to address this issue. The vulnerability does not appear to be actively exploited at this time.

Key Points: • Postfix vulnerability allows denial of service via crafted network traffic. • Affected Ubuntu versions include 26.04 LTS, 25.10, 24.04 LTS, and 22.04 LTS. • Users should update to the latest Postfix package versions to mitigate risks.

ThreatCluster AI

Timeline

2026-05-04
CVE-2026-43964 published
A denial of service vulnerability in Postfix was officially published, detailing the flaw's potential impact.
Linuxsecurity
2026-05-07
Vulnerability disclosed
Kamil Frankowicz disclosed that Postfix incorrectly handled enhanced status codes, allowing crashes.
Ubuntu
2026-05-07
Patch recommendation issued
Users are urged to update to the latest Postfix versions to prevent potential denial of service attacks.
Ubuntu

Community

Browse all →

Tracked Entities in This Story