Rule History

alert http any any -> $HOME_NET any (msg:"ET WEB_SPECIFIC_APPS Microsoft Sharepoint WebPartPages Authenticated Remote Code Execution (CVE-2021-28474)"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/_vti_bin/WebPartPages.asmx"; fast_pattern; http.request_body; pcre:"/[rR][uU][nN][aA][tT](?:\x3d|\x253[dD]|\x26equals\x3b)(?:\x22|\x2522|\x26quot\x3b)server(?:\x22|\x2522|\x26quot\x3b)/"; content:"OuterHtml|3d|"; content:"|2f|web.config"; distance:0; reference:url,www.zerodayinitiative.com/blog/2021/7/7/cve-2021-28474-sharepoint-remote-code-execution-via-server-side-control-interpretation-conflict; reference:cve,2021-28474; classtype:web-application-attack; sid:2063645; rev:2; metadata:affected_product Microsoft_Sharepoint, attack_target Server, tls_state TLSDecrypt, created_at 2025_07_21, cve CVE_2021_28474, deployment Perimeter, deployment Internal, confidence High, signature_severity Major, tag Exploit, updated_at 2025_07_22, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application; target:dest_ip;)