Stack-based buffer overflow in the split_wildmats function in nntpd.c in nntpd in Cyrus IMAP Server before 2.3.17 and 2.4.x before 2.4.11 allows remote attackers to execute arbitrary code via a crafted NNTP command.

The index_get_ids function in index.c in imapd in Cyrus IMAP Server before 2.4.11, when server-side threading is enabled, allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) via a crafted References header in an e-mail message.

The STARTTLS implementation in Cyrus IMAP Server before 2.4.7 does not properly restrict I/O buffering, which allows man-in-the-middle attackers to insert commands into encrypted sessions by sending a cleartext command that is processed after TLS is in place, related to a "plaintext command injection" attack, a similar issue to CVE-2011-0411.

Buffer overflow in proxyd for Cyrus IMAP Server 2.2.9 and earlier, with the imapmagicplus option enabled, may allow remote attackers to execute arbitrary code, a different vulnerability than CVE-2004-1011.

Off-by-one error in the mysasl_canon_user function in Cyrus IMAP Server 2.2.9 and earlier leads to a buffer overflow, which may allow remote attackers to execute arbitrary code via the username.