alert http $EXTERNAL_NET any -> $HTTP_SERVERS any (msg:"ET WEB_SERVER PHP SESSION SuperGlobal in URI"; flow:established,to_server; http.uri; content:"_SESSION["; fast_pattern; pcre:"/[&\?]_SESSION\[[^\]]+?\][^=]*?=/"; reference:url,imperva.com/download.asp?id=421; classtype:bad-unknown; sid:2017440; rev:4; metadata:created_at 2013_09_10, signature_severity Major, updated_at 2020_09_21;)