CVE-2026-27856

Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Figuring out the credential will lead into full access to the affected component. Limit access to the doveadm http service port, install fixed version. No publicly available exploits are known.

Affected products

Doveadm, Dovecot, Linuxmint, Red Os, Ubuntu

Dovecot

< 2.4.3

Open-xchange Dovecot

< 2.3.22.1, 3.0.5, 3.1.4

Fix

Available

CVSS 3.1

7.4 HIGH

EPSS

0.4% (33th percentile)

Weakness

CWE-287, CWE-208

NVD status

Modified

Published

2026-03-27