Format string vulnerability in imap4d server in GNU Mailutils 0.5 and 0.6, and other versions before 0.6.90, allows remote attackers to execute arbitrary code via format string specifiers in the command tag for IMAP commands.
http://www.securityfocus.com/bid/13764
http://www.idefense.com/application/poi/display?id=246&type=vulnerabilities
http://www.debian.org/security/2005/dsa-732