PT-2026-28367 · Dovecot+3 · Dovecot+3

Djvirus · CVE-2026-27859 · Published 2026-01-01 · Updated 2026-07-07

Positive Technologies (AI Summary)

CVSS v3.1

5.3

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Name of the Vulnerable Software and Affected Versions Dovecot versions prior to 2.4.3-1.1

Description A mail message with a large number of RFC 2231 MIME parameters can cause excessive CPU usage in LMTP. A specially crafted message can lead to significant CPU time consumption during mail delivery. No publicly available exploits are known.

Recommendations Upgrade to version 2.4.3-1.1 or later. Limit RFC 2231 MIME parameters in mail messages using MTA capabilities.

Exploit

Fix

DoS

Resource Exhaustion

Weakness Enumeration

CWE-400

Related Identifiers

BDU:2026-10406

CVE-2026-27859

OESA-2026-1849

OPENSUSE-SU-2026:10442-1

OPENSUSE-SU-2026:20554-1

SUSE-SU-2026:1641-1

SUSE-SU-2026:21208-1

USN-8136-1

Affected Products

Dovecot

Linuxmint

Red Os

Ubuntu

References · 65

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/27xxx/CVE-2026-27859.json · Exploit
• https://osv.dev/vulnerability/USN-8136-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-27860 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-27856 · Security Note
• https://osv.dev/vulnerability/OESA-2026-1849 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-24031 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-27859 · Security Note
• https://ubuntu.com/security/notices/USN-8136-1 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-27859 · Vendor Advisory
• https://bdu.fstec.ru/vul/2026-10406 · Security Note
• https://ubuntu.com/security/CVE-2026-27855 · Vendor Advisory
• https://osv.dev/vulnerability/ALPINE-CVE-2026-27859 · Vendor Advisory
• https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-59031 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-27859 · Vendor Advisory