CVE-2026-26312 (GCVE-0-2026-26312)

Vulnerability from cvelistv5 – Published: 2026-02-19 21:05 – Updated: 2026-02-20 19:58
VLAI
Title
Stalwart Mail Server has Out-of-Memory Denial of Service via Malformed Nested MIME Messages
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-20 19:57 UTC
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7993 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
stalwartlabs stalwart Affected: >= 0.13.0, < 0.15.5
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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