alert http any any -> [$HOME_NET,$HTTP_SERVERS] any (msg:"ET EXPLOIT Citrix ShareFile Storage Zones Controller RCE Attempt (CVE-2021-22941)"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/upload.aspx"; content:"id"; content:"|40|"; distance:0; content:"|2e 2e 2f|"; distance:0; content:"|2e|cshtml"; distance:0; fast_pattern; content:"bp"; content:"accountid"; http.header_names; to_lowercase; content:"|0d 0a|content-type|0d 0a|"; reference:cve,2021-22941; classtype:attempted-admin; sid:2034972; rev:3; metadata:attack_target Server, created_at 2022_01_25, cve CVE_2021_22941, deployment Perimeter, deployment Internal, confidence High, signature_severity Major, tag Exploit, tag CISA_KEV, updated_at 2024_04_25, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;)