#VU124727 Resource exhaustion in Dovecot and OX Dovecot Pro - CVE-2026-27859

 

#VU124727 Resource exhaustion in Dovecot and OX Dovecot Pro - CVE-2026-27859

Published: April 1, 2026


Vulnerability identifier: #VU124727
Vulnerability risk: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L/E:U/U:Green
CVE-ID: CVE-2026-27859
CWE-ID: CWE-400
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vulnerable software:
Dovecot
OX Dovecot Pro
Software vendor:
Dovecot

Description

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to uncontrolled resource consumption in MIME parameter parsing when processing message headers. A remote attacker can send a specially crafted email message with excessive RFC 2231 MIME parameters to cause a denial of service of the LMTP mail delivery process.


Remediation

Install security update from vendor's website.

External links