Multiple stack-based buffer overflows in the legacy mod_jk2 2.0.3-DEV and earlier Apache module allow remote attackers to execute arbitrary code via a long (1) Host header, or (2) Hostname within a Host header.
https://www.exploit-db.com/exploits/5386
https://www.exploit-db.com/exploits/5330
http://www.vupen.com/english/advisories/2008/0572
http://www.securityfocus.com/bid/27752
http://www.securityfocus.com/archive/1/487983/100/100/threaded