alert http $HOME_NET any -> $EXTERNAL_NET any (
msg:"ET MALWARE OtterCookie File Exfiltration M2";
flow:established,to_server;
http.method;
content:"POST";
http.uri; bsize:7;
content:"/upload";
http.header_names;
content:"|0d 0a|userkey|0d 0a|"; fast_pattern;
content:"|0d 0a|hostname|0d 0a|";
content:"|0d 0a|path|0d 0a|";
content:"|0d 0a|t|0d 0a|";
http.user_agent;
content:"axios/";
http.request_body;
content:"Content-Disposition|3a 20|form-data|3b 20|name|3d 22|file|22 3b 20|filename|3d 22|";
reference:url,blackpointcyber.com/blog/malicious-node-package-deploys-ottercookie/;
classtype:trojan-activity;
sid:2065863; rev:1;
metadata:affected_product Windows_XP_Vista_7_8_10_Server_32_64_Bit, affected_product Windows_11, attack_target Client_Endpoint, tls_state plaintext, created_at 2025_11_20, deployment Perimeter, malware_family OtterCookie, performance_impact Low, confidence High, signature_severity Major, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2025_11_20, mitre_tactic_id TA0009, mitre_tactic_name Collection, mitre_technique_id T1005, mitre_technique_name Data_from_local_system;
target:src_ip;
)