Legacy DAST Can’t Log In—And That Breaks Everything

Modern applications have evolved beyond traditional authentication methods, utilizing mechanisms such as OAuth2, OIDC, JSON Web Tokens, and API keys, yet many legacy Dynamic Application Security Testing (DAST) tools remain outdated, assuming authentication through web forms and session cookies. This misalignment causes a significant security gap, as these tools often fail to access and test the most critical parts of applications, such as admin panels and API endpoints, where 73% of vulnerabilities are found. The inability of legacy scanners to handle complex, token-based authentication flows leads to "security theater" where only public endpoints are tested, leaving the real attack surfaces unchecked. This creates false security confidence, wastes resources, and potentially delays development cycles, as authentication issues can break CI/CD pipelines and block deployments. The blog emphasizes the necessity for modern security scanners that can manage dynamic authentication processes to provide true security coverage and suggests that investments in such tools can mitigate significant business risks and compliance gaps.