The net/http library in net/http/transfer.go in Go before 1.4.3 does not properly parse HTTP headers, which allows remote attackers to conduct HTTP request smuggling attacks via a request with two Content-length headers.

Go is vulnerable to HTTP request smuggling, caused by a flaw in net/http library in net/textproto/reader.go. By sending a specially-crafted HTTP request with a space instead of a hyphen, an attacker could exploit this vulnerability to poison the web cache, bypass web application firewall protection, and conduct XSS attacks.