CVE-2011-1926 cyrus-imapd: STARTTLS plaintext command injection

Issue

• It was found, that Cyrus IMAP recognized IMAP, LMTP, NNTP and POP3 protocol commands during plaintex to TLS session switch (by TLS protocol initialization).
• A remote attacker could use this flaw to insert plaintext, protocol relevant, commands into TLS protocol initialization messages, leading to execution of these commands during the ciphertext protocol phase, potentially allowing the attacker to steal the victim's mail or authentication credentials.