alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET RETIRED Suspected TA399/SideWinder Phishing Activity - Landing Page URI Pattern"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/"; content:!"/"; distance:0; content:"-"; within:25; bsize:<33; pcre:"/^\/[a-zA-Z0-9]{1,25}\-[a-f0-9]{8}$/"; http.header_names; content:!"|0d 0a|Referer|0d 0a|"; http.header; content:"Sec-Fetch-Dest|3a 20|document|0d|"; fast_pattern; reference:url,blog.group-ib.com/sidewinder-antibot; reference:url,mp.weixin.qq.com/s/Kkta59k7r81uIBjJvE9pCw; classtype:targeted-activity; sid:2036785; rev:3; metadata:attack_target Client_and_Server, created_at 2022_06_02, deployment Perimeter, deployment SSLDecrypt, former_category MALWARE, malware_family Sidewinder, performance_impact Low, confidence Low, signature_severity Major, tag TA399, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_10_23, reviewed_at 2024_09_16;)