alert http $EXTERNAL_NET any -> $HOME_NET any (
msg:"ET WEB_SPECIFIC_APPS CrushFTP Authentication Bypass (CVE-2025-2825)";
flow:established,to_server;
http.uri;
content:"c2f|3d|";
byte_extract:4,0,c2f,relative;
http.header;
content:"authorization|3a 20|"; nocase;
content:"|20|credential|3d|"; nocase;
pcre:"/^[^\x7e\x2f\x0d\x0a]+\x2f/R";
http.cookie;
content:"CrushAuth|3d|"; fast_pattern;
pcre:"/^[0-9]{13}_[a-zA-Z0-9]{26}/R";
byte_test:4,=,c2f,0,relative;
reference:url,projectdiscovery.io/blog/crushftp-authentication-bypass;
reference:cve,2025-2825;
reference:cve,2025-31161;
classtype:web-application-attack;
sid:2061227; rev:1;
metadata:affected_product CrushFTP, attack_target Server, tls_state TLSDecrypt, created_at 2025_03_31, cve CVE_2025_2825, deployment Perimeter, deployment Internal, deployment SSLDecrypt, confidence High, signature_severity Major, tag Exploit, updated_at 2025_03_31, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;
target:dest_ip;
)