Alternatives to Kong for LLM gateway boundary test

What middleBrick covers

Black-box scanning with no agents or SDK dependencies
18 LLM adversarial probes across Quick, Standard, and Deep tiers
OpenAPI 3.0/3.1 and Swagger 2.0 contract validation
Authenticated scans with header allowlist and domain verification
Read-only testing with sensitive endpoint blocking
Findings mapped to OWASP API Top 10, SOC 2 Type II, and PCI-DSS 4.0

Purpose and scope for LLM gateway boundary testing

This tool targets LLM gateway scenarios where user prompts traverse an API boundary before reaching the model. It focuses on what an external or internal API surface exposes to an LLM, such as prompt injection, instruction override, and data exfiltration attempts. The scanner does not test the LLM itself or the model internals; it assesses the API controls that sit in front of the LLM.

LLM security probe coverage

The scanner includes 18 adversarial probes executed across three scan tiers: Quick, Standard, and Deep. These probes test for system prompt extraction, instruction override, DAN and roleplay jailbreaks, data exfiltration, cost exploitation, and encoding bypass techniques such as base64 and ROT13. Additional checks include translation-embedded injection, few-shot poisoning, markdown injection, multi-turn manipulation, indirect prompt injection, token smuggling, tool-abuse patterns, nested instruction injection, and PII extraction.

OpenAPI contract validation for LLM endpoints

The scanner parses OpenAPI 3.0, 3.1, and Swagger 2.0 documents with recursive $ref resolution. It cross-references spec definitions against runtime behavior to surface undefined security schemes, deprecated operations, missing pagination, and oversensitive field exposure. This helps identify mismatches between documented and actual gateway behavior that could weaken LLM boundary controls.

Authenticated scanning requirements and safety constraints

Authenticated scans support Bearer, API key, Basic auth, and Cookie credentials, and they require domain verification via DNS TXT record or a well-known HTTP file to ensure only the domain owner can submit credentials. The scanner enforces a strict header allowlist including Authorization, X-API-Key, Cookie, and X-Custom-* headers. All testing is read-only, with destructive payloads never sent, and sensitive endpoints such as private IPs, localhost, and cloud metadata are blocked at multiple layers.

How findings align to compliance frameworks

Findings map directly to OWASP API Top 10 (2023), providing evidence that supports audits aligned with SOC 2 Type II and PCI-DSS 4.0. For other frameworks, the scanner surfaces findings relevant to audit evidence and helps you prepare for security controls described in HIPAA, GDPR, ISO 27001, NIST, CCPA, and similar regulations without asserting compliance guarantees.

Frequently Asked Questions

Can this scanner test my LLM model directly for jailbreaks?

No. The scanner tests the API boundary in front of the LLM, not the model itself. It checks whether the API exposes controls that can be bypassed via prompt injection or instruction override techniques.

Does authenticated scanning require code access or SDK integration?

No. The scanner is black-box and requires only credentials for domain-verified authenticated scans. No agents, SDKs, or code changes are necessary.

What happens to scan data after I cancel the service?

Customer scan data is deletable on demand and is purged within 30 days of cancellation. It is never sold and is not used for model training.

Can the scanner detect business logic flaws in LLM workflows?

No. Business logic vulnerabilities that require domain-specific understanding are outside the scope of automated scanning. These should be evaluated by a human security expert familiar with your application context.