CVE-2026-27859: Medium severity Dovecot dovecot vulnerability
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 Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-27859?
The severity of CVE-2026-27859 is medium, with a score of 5.3.
What are the main impacts of CVE-2026-27859?
CVE-2026-27859 can lead to excessive CPU consumption by the LMTP mail delivery process.
How do I fix CVE-2026-27859?
To fix CVE-2026-27859, you should use MTA capabilities to limit RFC 2231 MIME parameters in email messages or upgrade to a fixed version of the software.
Which software is affected by CVE-2026-27859?
CVE-2026-27859 affects Open-Xchange Dovecot and Dovecot software.
When was CVE-2026-27859 published?
CVE-2026-27859 was published on March 27, 2026.