Stalwart is a mail and collaboration server. A denial-of-service vulnerability exists in Stalwart Mail Server versions 0.13.0 through 0.15.4 where accessing a specially crafted email containing malformed nested `message/rfc822` MIME parts via IMAP or JMAP causes excessive CPU and memory consumption, potentially leading to an out-of-memory condition and server crash. The malformed structure causes the `mail-parser` crate to produce cyclical references in its parsed representation, which Stalwart then follows indefinitely. Version 0.15.5 contains a patch.
History

Thu, 19 Feb 2026 21:15:00 +0000

Type Values Removed Values Added
Description Stalwart is a mail and collaboration server. A denial-of-service vulnerability exists in Stalwart Mail Server versions 0.13.0 through 0.15.4 where accessing a specially crafted email containing malformed nested `message/rfc822` MIME parts via IMAP or JMAP causes excessive CPU and memory consumption, potentially leading to an out-of-memory condition and server crash. The malformed structure causes the `mail-parser` crate to produce cyclical references in its parsed representation, which Stalwart then follows indefinitely. Version 0.15.5 contains a patch.
Title Stalwart Mail Server has Out-of-Memory Denial of Service via Malformed Nested MIME Messages
Weaknesses CWE-770
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-02-19T21:05:11.788Z

Reserved: 2026-02-13T16:27:51.806Z

Link: CVE-2026-26312

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-02-19T21:18:31.823

Modified: 2026-02-19T21:18:31.823

Link: CVE-2026-26312

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.