ELM : When we click on upgrade and try to browse we get the error : there was an error on processing web request : status code 400 (bad Request ) : Bad Request

Error : there was an error on processing web request : status code 400 bad Request : Bad Request...

Apache Httpd < 2.0.65 : error responses can expose cookies

A flaw was found in the default error response for status code 400. This flaw could be used by an attacker to expose "httpOnly" cookies when no custom ErrorDocument is specified...