alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MOBILE_MALWARE Kimsuky AppleSeed CnC Checkin"; flow:established,to_server; http.method; content:"POST"; http.uri; content:".php?m="; fast_pattern; content:"&p1="; distance:1; within:4; content:"&p2="; distance:16; within:4; pcre:"/\.php\?m=[abcdefgh]&p1=[a-f0-9]{16}&p2=[^\r\n]+$/"; http.user_agent; content:"Android"; http.content_len; content:"0"; bsize:1; http.header_names; content:!"Referer"; reference:url,blog.malwarebytes.com/threat-analysis/2021/06/kimsuky-apt-continues-to-target-south-korean-government-using-appleseed-backdoor; reference:md5,4626ed60dfc8deaf75477bc06bd39be7; classtype:trojan-activity; sid:2033059; rev:1; metadata:affected_product Android, attack_target Mobile_Client, created_at 2021_06_01, deployment Perimeter, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_06_01, mitre_tactic_id TA0010, mitre_tactic_name Exfiltration, mitre_technique_id T1041, mitre_technique_name Exfiltration_Over_C2_Channel;)