CVE-2026-27859
5.3
MEDIUM
CVSS 3.1
EPSS 0.03%
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.
How to fix CVE-2026-27859
To remediate CVE-2026-27859, upgrade the affected package to a fixed version below.
- —upgrade to 2.4.3-r0 or later
- —upgrade to 1:2.3.13+dfsg1-2+deb11u3 or later
Is CVE-2026-27859 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (2)
- from 0, < 2.4.3-r0
- from 0, < 1:2.3.13+dfsg1-2+deb11u3
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |