CVE-2026-27859

Publication date 27 March 2026

Last updated 30 March 2026


Ubuntu priority

Cvss 3 Severity Score

5.3 · Medium

Score breakdown

Description

v3.0.2+ regression: Message headers MIME parameter parsing can cause excessive CPU usage. A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU. A suitably formatted mail message causes mail delivery process to consume large amounts of CPU time. No publicly available exploits are known.

Status

Package Ubuntu Release Status
dovecot 25.10 questing
Vulnerable
24.04 LTS noble
Vulnerable
22.04 LTS jammy
Vulnerable
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial
Vulnerable
14.04 LTS trusty
Vulnerable

Severity score breakdown

Parameter Value
Base score 5.3 · Medium
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact Low
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Access our resources on patching vulnerabilities