alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET ADWARE_PUP Fake Adobe Update Download"; flow:established,to_client; http.stat_code; content:"200"; http.header; content:"filename=readerdc"; fast_pattern; nocase; pcre:"/(_[a-z]{2}){1,3}_[a-z]{3}_install\.exe/Ri"; content:!"Server|3a 20 20|Apache"; content:"Set-Cookie|3a 20|session="; classtype:pup-activity; sid:2026734; rev:4; metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, attack_target Client_Endpoint, created_at 2018_12_17, deployment Perimeter, confidence High, signature_severity Minor, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_08_31;)