Rule History

SID: 2033682 • Source: et/open

Versions (5)

Version DetailsCurrent

Rev: 2 • Aug 9, 2021, 12:00 PM

Message:

ET EXPLOIT Microsoft Exchange Pre-Auth Path Confusion M2 (CVE-2021-31207)

Rule:

alert http any any -> [$HOME_NET,$HTTP_SERVERS] any (msg:"ET EXPLOIT Microsoft Exchange Pre-Auth Path Confusion M2 (CVE-2021-31207)"; flow:established,to_server; http.uri; content:"/autodiscover?"; nocase; content:"/mapi/nspi"; nocase; distance:0; fast_pattern; http.cookie; content:"Email=autodiscover/"; nocase; flowbits:set,ET.cve.2021.34473; reference:cve,2021-31207; classtype:attempted-admin; sid:2033682; rev:2; metadata:affected_product Microsoft_Exchange, attack_target Server, created_at 2021_08_09, cve CVE_2021_31207, deployment Perimeter, deployment Internal, deployment SSLDecrypt, confidence High, signature_severity Major, tag Exploit, tag CISA_KEV, 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;)

Created:

Aug 9, 2021, 12:00 PM

Updated:

Dec 23, 2022, 12:00 PM

DB Created:

Sep 21, 2024, 3:00 AM

DB Updated:

May 30, 2025, 12:04 AM

Filename:

rules/emerging-exploit.rules