|The Apache HTTP server before 1.3.34, and 2.0.x before 2.0.55, when
acting as an HTTP proxy, allows remote attackers to poison the web
cache, bypass web application firewall protection, and conduct XSS
attacks via an HTTP request with both a "Transfer-Encoding: chunked"
header and a Content-Length header, which causes Apache to incorrectly
handle and forward the body of the request in a way that causes the
receiving server to process it as a separate HTTP request, aka "HTTP