alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET INFO POSSIBLE Crawl using Fetch"; flow:established,to_server; threshold:type both, track by_src, count 10, seconds 60; http.user_agent; content:"fetch"; depth:50; nocase; reference:url,gobsd.com/code/freebsd/lib/libfetch; classtype:attempted-recon; sid:2002827; rev:12; metadata:created_at 2010_07_30, confidence High, signature_severity Informational, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_04_23;)