alert http any any -> [$HOME_NET,$HTTP_SERVERS] any (
msg:"ET EXPLOIT NodeJS System Information Library Command Injection Attempt (CVE-2021-21315)";
flow:established,to_server;
http.method;
content:"GET";
http.uri;
content:"/api/getServices?name"; fast_pattern; startswith;
pcre:"/^.*\x3d[^\x26]*?(?:(?:\x3b|%3[Bb])|(?:\x0a|%0[Aa])|(?:\x60|%60)|(?:\x7c|%7[Cc])|(?:\x24|%24))+/R";
reference:cve,2021-21315;
reference:url,github.com/ForbiddenProgrammer/CVE-2021-21315-PoC;
classtype:attempted-admin;
sid:2034973; rev:3;
metadata:affected_product Node_js, attack_target Web_Server, created_at 2022_01_25, cve CVE_2021_21315, deployment Perimeter, deployment Internal, performance_impact Low, confidence High, signature_severity Major, tag Exploit, tag CISA_KEV, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2026_08_20, mitre_tactic_id TA0008, mitre_tactic_name Lateral_Movement, mitre_technique_id T1210, mitre_technique_name Exploitation_Of_Remote_Services;
target:dest_ip;
)