alert tcp $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Vicious Panda Checkin"; flow:established,to_server; dsize:50<>400; content:"|46 45 79 4e 56 59 6c 63 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00|"; fast_pattern; reference:md5,07328ad6efcf16b532499cbb8daa7633; reference:url,research.checkpoint.com/2020/vicious-panda-the-covid-campaign/; reference:url,twitter.com/dewan202/status/1244595728175030272; classtype:trojan-activity; sid:2030920; rev:1; metadata:attack_target Client_Endpoint, created_at 2020_09_29, deployment Perimeter, deployment SSLDecrypt, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2020_09_29;)