CVE-2026-27859CWE-400

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

Medium · published March 27, 2026

CVSS v3.1
5.3
EPSS
0%
Percentile
33.3
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CVSS v4.0
Not supplied
EPSS
0.00402 · 33.3th percentile
Weakness
CWE-400 · Uncontrolled Resource Consumption
Published
2026-03-27T08:10Z
EPSS history
Timeline
  • 27 MAR 08:10Z
    A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU
    cvelistv5