Rule History

alert smtp any any -> [$HOME_NET,$HTTP_SERVERS,$SMTP_SERVERS] any (msg:"ET EXPLOIT Exim receive_msg Integer Overflow Attempt Inbound M2 (CVE-2020-28020)"; flow:established,to_server; content:"|0a 09|"; content:"|0a 0a 0a 0a 0a 0a 0a 0a 0a 0a 0a 0a 0a 0a 0a 0a 0a|"; fast_pattern; isdataat:50000,relative; reference:url,www.qualys.com/2021/05/04/21nails/21nails.txt; reference:cve,2020-28020; classtype:attempted-admin; sid:2032899; rev:1; metadata:attack_target SMTP_Server, created_at 2021_05_04, cve CVE_2020_28020, deployment Perimeter, deployment Internal, confidence Medium, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_05_04;)