alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET HUNTING SUSPICIOUS Excel Add-in Download M2"; flow:to_server,established; http.header; content:".xla"; nocase; pcre:"/Content-Disposition\x3a[^\r\n]*?\.xla[\s\x22\x27]/i"; reference:url,blogs.mcafee.com/mcafee-labs/patch-now-simple-office-protected-view-bypass-could-have-big-impact/; classtype:bad-unknown; sid:2022966; rev:3; metadata:created_at 2016_07_13, confidence Medium, signature_severity Informational, updated_at 2020_07_17;)