DSSRF is a Node.js library that provides a wide range of utilities and advanced SSRF defense checks. Prior to 1.0.4, is_url_safe in src/helpers.ts strips the @ userinfo delimiter with remove_at_symbol_in_string before new URL parses the URL, allowing an attacker-controlled URL to bypass internal-IP validation and cause a client using the original URL to reach an internal service. This issue is fixed in version 1.0.4.