Multiple unspecified vulnerabilities in MDaemon and WorldClient in Alt-N Technologies MDaemon before 9.50 allow attackers to cause a denial of service (memory consumption) via unspecified vectors resulting in memory leaks.

Multiple heap-based buffer overflows in the POP3 server in Alt-N Technologies MDaemon before 9.0.6 allow remote attackers to cause a denial of service (daemon crash) and possibly execute arbitrary code via long strings that contain '@' characters in the (1) USER and (2) APOP commands.

Buffer overflow in Alt-N MDaemon, possibly 9.0.1 and earlier, allows remote attackers to execute arbitrary code via a long A0001 argument that begins with a '"' (double quote).

Multiple buffer overflows in MDaemon 6.5.1 allow remote attackers to cause a denial of service (application crash) via a long (1) SAML, SOML, SEND, or MAIL command to the SMTP server or (2) LIST command to the IMAP server.