CVE-2026-27859

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. Use MTA capabilities to limit RFC 2231 MIME parameters in mail messages, or upgrade to fixed version where the processing is limited. No publicly available exploits are known.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:dovecot:dovecot::::::::
	cpe:2.3:a:open-xchange:dovecot:::::pro:::*
	cpe:2.3:a:open-xchange:dovecot:::::pro:::*

History

26 Oct 2026, 00:10

Type	Values Removed	Values Added
Summary		(es) Un mensaje de correo que contiene una cantidad excesiva de parámetros MIME RFC 2231 provoca que LMTP utilice demasiada CPU. Un mensaje de correo formateado adecuadamente provoca que el proceso de entrega de correo consuma grandes cantidades de tiempo de CPU. Utilice las capacidades del MTA para limitar los parámetros MIME RFC 2231 en los mensajes de correo, o actualice a una versión corregida donde el procesamiento está limitado. No se conocen exploits disponibles públicamente.

Information

Published : 2026-03-27 09:16

Updated : 2026-10-26 00:10

NVD link : CVE-2026-27859

Mitre link : CVE-2026-27859

CVE.ORG link : CVE-2026-27859

JSON object : View

Products Affected

open-xchange

dovecot

dovecot

dovecot

CWE

CWE-400

Uncontrolled Resource Consumption

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