alert http any any -> [$HOME_NET,$HTTP_SERVERS] any (msg:"ET EXPLOIT Atlassian Confluence Pre-Authorization Arbitrary File Read Attempt (CVE-2021-26085)"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/s/123cfx/_/|3b|/"; nocase; fast_pattern; pcre:"/^(?:META-INF\x2fmaven\x2fcom.atlassian.confluence\x2fconfluence-webapp\x2f(?:pom.xml|pom.properties)|WEB-INF\x2f(?:classes\x2fseraph-config.xml|web.xml))/R"; http.header_names; content:!"cookie|0d 0a|"; nocase; content:!"authorization|0d 0a|"; nocase; reference:url,packetstormsecurity.com/files/164401/Atlassian-Confluence-Server-7.5.1-Arbitrary-File-Read.html; reference:cve,2021-26085; classtype:attempted-admin; sid:2034150; rev:2; metadata:affected_product Atlassian_Confluence, attack_target Server, tls_state TLSDecrypt, created_at 2021_10_07, cve CVE_2021_26085, deployment Perimeter, deployment Internal, confidence High, signature_severity Major, tag Exploit, tag CISA_KEV, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2026_08_28, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application; target:dest_ip;)