CVE-2026-27856

EUVD-2026-16565
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.4 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
OXCNA
7.4 HIGH
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Debian logo
Debian Releases
Debian Product
Codename
dovecot
bookworm
vulnerable
bookworm (security)
vulnerable
bullseye
vulnerable
bullseye (security)
vulnerable
forky
vulnerable
sid
vulnerable
trixie
vulnerable
trixie (security)
vulnerable
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
dovecot
bionic
not-affected
focal
needed
jammy
needed
noble
needed
questing
needed
trusty
not-affected
xenial
not-affected