Fetchmail (aka fetchmail-ssl) before 5.8.17 allows a remote malicious (1) IMAP server or (2) POP/POP3 server to overwrite arbitrary memory and possibly gain privileges via a negative index number as part of a response to a LIST request.
archives.neohapsis.com/archives/bugtraq/2001-08/0118.html
distro.conectiva.com.br/atualizacoes/?id=a&anuncio=000419
www.debian.org/security/2001/dsa-071
www.iss.net/security_center/static/6965.php
www.linux-mandrake.com/en/security/2001/MDKSA-2001-072.php3
www.linuxsecurity.com/advisories/other_advisory-1555.html
www.novell.com/linux/security/advisories/2001_026_fetchmail_txt.html
www.redhat.com/support/errata/RHSA-2001-103.html
www.securityfocus.com/bid/3164
www.securityfocus.com/bid/3166