alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET ADWARE_PUP Adware.InstallCore.B Checkin"; flow:established,to_server; urilen:13<>18; http.method; content:"POST"; http.uri; content:"/?pcrc="; fast_pattern; pcre:"/^\/\?pcrc=[0-9]{7,10}$/"; http.request_body; content:"0A0Czut"; depth:7; http.header_names; content:!"Referer|0d 0a|"; reference:md5,d933bef7e1118b181add31eb5edc5c73; classtype:pup-activity; sid:2019511; rev:8; metadata:created_at 2014_10_27, signature_severity Minor, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_10_12;)