CVE-2026-33607

Medium

Description

An attacker that has valid credentials can use IMAP LIST command to consume CPU. This can cause degradation or denial of service for IMAP. Monitor system for abnormal CPU usage and kill the offending process and lock account. Alternatively install fixed version. No publicly available exploits are known.

SeverityMedium

CVSS4.3

Exploit probability—

ProductOX Dovecot Pro

PublishedAug 28, 2026

First seenAug 28, 2026

Weakness typeCWE-400Uncontrolled resource consumption

How to fix

Update

Open-Xchange GmbH OX Dovecot Pro3.0.7, 3.1.6 or later
Open-Xchange GmbH OX Dovecot CE2.4.5 or later

Vendor advisories

documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0003.json

Affected products

Product	Affected versions	Fixed in
Open-Xchange GmbH OX Dovecot Pro	2.3.0 ≤ v < 3.0.7, 3.1.0 ≤ v < 3.1.6	3.0.7, 3.1.6
Open-Xchange GmbH OX Dovecot CE	2.3.0 ≤ v < 2.4.5	2.4.5

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