Rule History

alert http any any -> [$HOME_NET,$HTTP_SERVERS,$SMTP_SERVERS] any (msg:"ET EXPLOIT Microsoft Exchange Remote Code Execution Attempt - OWASSRF (CVE-2022-41040, CVE-2022-41082)"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/owa/"; startswith; nocase; content:"@"; distance:0; content:"/powershell"; endswith; nocase; fast_pattern; http.user_agent; content:!"ClientInfo"; content:!"Microsoft WinRM Client"; content:!"Exchange BackEnd Probes"; http.request_body; content:"|3c|s|3a|Envelope|20|xmlns|3a|rsp|3d 22|"; startswith; content:"wbem/wsman/1/windows/shell|22|"; within:100; content:"|3c|wsa|3a|To|3e|"; distance:0; content:"|3c|s|3a|Body|3e 3c|rsp|3a|Shell|20|ShellId|3d 22|"; distance:0; reference:url,www.crowdstrike.com/blog/owassrf-exploit-analysis-and-recommendations/; reference:url,github.com/CrowdStrike/OWASSRF/blob/main/Rps_Http-IOC.ps1; reference:cve,2022-41040; reference:cve,2022-41082; classtype:attempted-admin; sid:2043002; rev:1; metadata:affected_product Microsoft_Exchange, attack_target Server, created_at 2022_12_23, cve CVE_2022_41040_CVE_2022_41082, deployment Perimeter, deployment SSLDecrypt, confidence High, signature_severity Major, tag ProxyNotShell, tag CISA_KEV, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2022_12_23, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application;)