alert http $EXTERNAL_NET any -> $HOME_NET any (msg:"ET EXPLOIT IE MSHTML Out-of-Bounds Write Inbound (CVE-2021-33742)"; flow:from_server,established; file.data; content:"innerHTML|20|=|20|Array|28|"; nocase; fast_pattern; byte_test:0,>=,33554431,0,string,dec,relative; content:"|29|.toString|28 29 3b|"; distance:0; within:50; reference:url,googleprojectzero.github.io/0days-in-the-wild/0day-RCAs/2021/CVE-2021-33742.html; reference:cve,2021-33742; classtype:attempted-admin; sid:2033326; rev:1; metadata:created_at 2021_07_15, cve CVE_2021_33742, confidence Medium, signature_severity Major, tag CISA_KEV, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_07_15;)