alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET INFO FUNNULL CDN System Error (GET)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/system/error"; startswith; http.host; bsize:15; content:"cdn.funnull.com"; fast_pattern; reference:url,silentpush.com/blog/infrastructure-laundering/; reference:url,silentpush.com/blog/triad-nexus-funnull/; classtype:bad-unknown; sid:2061982; rev:1; metadata:attack_target Client_Endpoint, created_at 2025_04_29, deployment Perimeter, confidence High, signature_severity Informational, updated_at 2025_04_29;)