alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET MALWARE APT Operation Sidecopy lnk Activity (GET)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/font/js/images/"; startswith; fast_pattern; content:"/css"; endswith; http.header_names; content:!"Referer"; content:"|0d 0a|Host|0d 0a|Connection|0d 0a 0d 0a|"; http.host; content:".in"; endswith; reference:url,twitter.com/ShadowChasing1/status/1406959698142666756; reference:md5,e05468aaa0c436e953116989ccf9703b; classtype:trojan-activity; sid:2033153; rev:1; metadata:attack_target Client_Endpoint, created_at 2021_06_21, deployment Perimeter, deployment SSLDecrypt, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2021_06_21;)