CVE-2026-27859 - Vulnerability Details - OpenCVE

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.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact Low

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

The EPSS score is 0.00039.

Exploitation none

Automatable yes

Technical Impact partial

No data.

No data.

No data.

No data.

Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References

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

History

Fri, 27 Mar 2026 13:15:00 +0000

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}`

Fri, 27 Mar 2026 08:30:00 +0000

Type	Values Removed	Values Added
Description		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.
Weaknesses		CWE-400
References		https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json
Metrics		cvssV3_1 `{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'}`

Projects

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MITRE

Status: PUBLISHED

Assigner: OX

Published: 2026-03-27T08:10:22.058Z

Updated: 2026-03-27T12:35:14.776Z

Reserved: 2026-02-24T08:46:09.374Z

Link: CVE-2026-27859

Vulnrichment

Updated: 2026-03-27T12:34:38.422Z

NVD

Status : Received

Published: 2026-03-27T09:16:20.223

Modified: 2026-03-27T09:16:20.223

Link: CVE-2026-27859

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-400

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