alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE CryptoWall Check-in M2"; flow:established,to_server; urilen:<110; http.uri; pcre:"/[\/=][a-z0-9]{8,}$/"; http.header; content:" rv|3a|11.0"; fast_pattern; content:"Accept|3a 20|*/*|0d 0a|Content-Type|3a 20|application/x-www-form-urlencoded|0d 0a|"; depth:62; http.request_body; content:"="; offset:1; depth:1; pcre:"/^[a-z]=[a-f0-9]{80,}$/"; http.header_names; content:!"|0d 0a|Accept-"; nocase; content:!"Referer|0d 0a|"; reference:md5,3c53c9f7ab32a09de89bb44e5f91f9af; classtype:trojan-activity; sid:2020855; rev:6; metadata:created_at 2015_04_08, performance_impact Significant, signature_severity Major, updated_at 2024_04_15;)