CVE-2026-27858 HIGH

CVE-2026-27858

Vendor Open-Xchange Gmbh
Product OX Dovecot Pro
Weakness CWE-400
Published March 27, 2026
Last update June 30, 2026

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install fixed version. No publicly available exploits are known.

Key dates

02Disclosure timeline

March 27, 2026 CVE published
June 30, 2026 Record updated