DSSRF is a Node.js library that provides a wide range of utilities and advanced SSRF defense checks. Prior to 1.0.5, is_url_safe can treat localhost as safe when DNS resolver 1.1.1.1 returns NXDOMAIN because dns.resolve4 yields no address and no dns.lookup fallback occurs, allowing server-side request forgery. This issue is fixed in version 1.0.5.
