HIGH ssrfbearer tokens

Ssrf with Bearer Tokens

Bearer Tokens-Specific Remediation

Remediating Bearer token SSRF vulnerabilities requires a defense-in-depth approach that addresses both the SSRF root cause and the token handling issues.

First, implement strict URL validation and allowlisting:

 

Related CWEs: ssrf

CWE IDNameSeverity
CWE-918Server-Side Request Forgery (SSRF) CRITICAL
CWE-441Unintended Proxy or Intermediary (Confused Deputy) HIGH

Frequently Asked Questions

How can I test if my Bearer token API endpoint is vulnerable to SSRF?
Test with SSRF payloads like http://127.0.0.1:8080, http://169.254.169.254/latest/meta-data/, and http://internal-service.local. Use middleBrick's automated scanning which tests these patterns and checks if your endpoint makes requests to internal services using the Bearer token. The scanner also verifies if tokens are forwarded in outbound requests and if responses contain sensitive data.
What's the difference between SSRF and traditional API attacks when Bearer tokens are involved?
Traditional API attacks target the API directly with stolen tokens, while SSRF exploits the server's ability to make outbound requests. With Bearer tokens, SSRF is particularly dangerous because it can bypass IP allowlisting, access internal services that aren't exposed to the internet, and use the token in contexts the attacker can't directly reach. SSRF can also expose tokens through error responses and metadata service access.