alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE Lazarus APT Related VSingle Backdoor Activity (GET)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:".php?uid="; pcre:"/^[0-9]{8}/R"; content:"&upw="; fast_pattern; distance:0; pcre:"/^(?:[A-Za-z0-9]{4})*(?:[A-Za-z0-9]{2}==|[A-Za-z0-9]{3}=|[A-Za-z0-9]{4})$/R"; http.user_agent; content:"Linux|20|"; http.header_names; content:!"Referer"; reference:md5,7ce51b56a6b0f8f78056ddfc5b5de67c; reference:url,blogs.jpcert.or.jp/en/2022/07/vsingle.html; classtype:trojan-activity; sid:2037276; rev:1; metadata:attack_target Client_Endpoint, created_at 2022_07_05, deployment Perimeter, malware_family Lazarus, malware_family Stonefly, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_07_06;)