CVE-2025-59028

Publication date 27 March 2026

Last updated 27 March 2026


Ubuntu priority

Description

Invalid base64 authentication can cause DoS for other logins. When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active authentication sessions to fail. Invalid BASE64 data can be used to DoS a vulnerable server to break concurrent logins. No publicly available exploits are known.

Read the notes from the security team

Status

Package Ubuntu Release Status
dovecot 25.10 questing
Vulnerable
24.04 LTS noble
Not affected
22.04 LTS jammy
Not affected
20.04 LTS focal
Not affected
18.04 LTS bionic
Not affected
16.04 LTS xenial
Not affected
14.04 LTS trusty
Not affected

Notes


ebarretto

Introduced by: https://github.com/dovecot/core/commit/1486c30e191ff079bfa78e7950173bb33d8073d9


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