CVE-2006-2659: Double Precision Incorporated Courier MTA

High severity, CVSS 7.8. EPSS: 2.4% chance of exploitation in the next 30 days.

libs/comverp.c in Courier MTA before 0.53.2 allows attackers to cause a denial of service (CPU consumption) via unknown vectors involving usernames that contain the "=" (equals) character, which is not properly handled during encoding.

Affected products

• Double Precision Incorporated Courier MTA: up to and including 0.44.2; version 0.37.3 only; version 0.38.1 only; version 0.40 only; version 0.43 only; version 0.43.1 only; …

Published 2006-05-30. Last modified 2026-06-16.