alert http $HOME_NET any -> $EXTERNAL_NET any (msg:"ET EXPLOIT Jira Server/Data Center 8.4.0 Remote File Read Attempt (CVE-2021-26086) M1"; flow:established,to_server; http.method; content:"GET"; http.uri; content:"/s/"; startswith; content:"|2f 5f 2f 3b 2f|WEB|2d|INF"; within:25; fast_pattern; pcre:"/(?:web|decorators|seraph-config)\x2exml$/R"; http.header_names; content:!"Referer"; reference:url,jira.atlassian.com/browse/JRASERVER-72695; reference:url,github.com/ColdFusionX/CVE-2021-26086; reference:cve,2021-26086; classtype:attempted-admin; sid:2038672; rev:2; metadata:affected_product Atlassian, attack_target Web_Server, created_at 2022_08_30, cve CVE_2021_26086, deployment Perimeter, deployment SSLDecrypt, deprecation_reason Relevance, confidence High, signature_severity Major, tag CISA_KEV, tag Description_Generated_By_Proofpoint_Nexus, updated_at 2024_12_02, reviewed_at 2024_12_02;)