A vulnerability was found in Ruby that allows HTTP header injection. A CGI application using the CGI library may insert untrusted input into the HTTP response header. This issue can allow an attacker to insert a newline character to split a header and inject malicious content to deceive clients.

A flaw was found in Ruby. RubyGems cgi gem could allow a remote attacker to conduct spoofing attacks caused by the mishandling of security prefixes in cookie names in the CGI::Cookie.parse function. By sending a specially-crafted request, an attacker could perform cookie prefix spoofing attacks.