A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

1. Mar 27, 2026 · NIST NVD

   Detected

   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.

2. Jun 17, 2026 · NIST NVD

   Updated

   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

• cpe dovecot/dovecotversion unspecified
• cpe open-xchange/dovecotversion unspecified

Sources

• CVE.orgVulnerability recordCVE-2026-27859

  Official CVE identifier

  cve.org
• NIST NVDVulnerability recordCVE-2026-27859

  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

  nvd.nist.gov

References

• Vendor Advisory · documentation.open-xchange.com