alert http $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"VEDAS CVE-2026-56771 NewsBlur - Server-Side Request Forgery via add_url"; flow:established,to_server; http.method; content:"POST"; http.uri; content:"/reader/add_url"; nocase; fast_pattern; http.request_body; content:"url"; nocase; pcre:"/https?(?:\x3a|%3a)(?:\x2f\x2f|%2f%2f)(?:127\.|0\.0\.0\.0|localhost|169\.254\.169\.254|metadata|10\.|192\.168\.|172\.(?:1[6-9]|2[0-9]|3[01])\.|\x5b|%5b)/i"; classtype:web-application-attack; reference:cve,CVE-2026-56771; reference:url,https://www.exploit.observer/?keyword=CVE-2026-56771&match=exact; reference:url,https://subdomain.center/?engine=ammonites&keyword=newsblur&match=exact; sid:1095406; rev:1;)