The fetchnews NNTP client in leafnode 1.9.3 to 1.9.41 allows remote attackers to cause a denial of service (process hang and termination) via certain malformed Usenet news articles that cause fetchnews to hang while waiting for input.
http://www.securityfocus.com/bid/8541
http://secunia.com/advisories/9678
http://marc.info/?l=bugtraq&m=106270038210736&w=2