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.
Affected products
dovecot: dovecot; open-xchange: dovecot
References1
- documentation.open-xchange.com/dovecot/security/advisories/csaf… Vendor Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - EPSS — exploit probability
- 0% percentile: 33 · as of 12 November 2026
- CWE
- CWE-400
Could this be exploited in your environment?
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