University Of Cambridge : Security Vulnerabilities, CVEs, Published In 2004 (Denial of service)

Stack-based buffer overflow in Exim 4 before 4.33, when the headers_check_syntax option is enabled, allows remote attackers to cause a denial of service and possibly execute arbitrary code during the header check.

Stack-based buffer overflow in Exim 3.35, and other versions before 4, when the sender_verify option is true, allows remote attackers to cause a denial of service and possibly execute arbitrary code during sender verification.