"There are several buffer overflows in imap, ipop2d and ipop3d. These overflows usually only make it possible for local users to gain access to a process running under their own UID.
However, due to a misconfiguration, it is possible for remote attackers to gain access to the 'nobody' account and run programs or further exploits on the attacked machine." Full details at Help Net Security.
March 13, 2001