CVE-2026-27858

HIGH 7.5

CVSS Score

7.5

EPSS Score

0.0%

EPSS Percentile

0th

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.

CWE	CWE-400
Vendor	open-xchange gmbh
Product	ox dovecot pro
Published	Mar 27, 2026
Last Updated	Jul 15, 2026

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CVSS v3 Breakdown

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Affected Versions

Open-Xchange GmbH / OX Dovecot Pro

0 ≤ 2.3.0 0 ≤ 3.1.0 0 ≤ 2.4.0

References

NVD ↗ CVE.org ↗ EPSS Data ↗