CVE-2017-2669: Debian Linux
High severity, CVSS 7.5. EPSS: 4.5% chance of exploitation in the next 30 days.
Dovecot before version 2.2.29 is vulnerable to a denial of service. When 'dict' passdb and userdb were used for user authentication, the username sent by the IMAP/POP3 client was sent through var_expand() to perform %variable expansion. Sending specially crafted %variable fields could result in excessive memory usage causing the process to crash (and restart), or excessive CPU usage causing all authentications to hang.
Affected products
Published 2018-06-21. Last modified 2026-06-17.