Best alternative to Intruder

For teams that need a self-service API security scanner without onboarding agents or granting code access, middleBrick is the strongest alternative to Intruder. It is a black-box scanner that submits a URL and returns a risk score from A to F with prioritized findings, completing a scan in under a minute using only read-only methods and text-only POST probes. Unlike Intruder, which focuses heavily on authenticated brute-force and injection payloads, middleBrick emphasizes API surface discovery, OWASP API Top 10 coverage, and structured reporting suited for automated pipelines. While Intruder remains useful for deep authenticated session-based attacks, middleBrick covers the broadest set of API-specific checks out of the box. Runners-up include specialized tools for schema fuzzing or legacy infrastructure, but they typically require more manual tuning or expose more risk surface than a read-only approach.

middleBrick maps findings to OWASP API Top 10 (2023), PCI-DSS 4.0, and SOC 2 Type II, providing clear audit evidence without claiming certification. It detects Authentication bypasses, JWT misconfigurations such as alg=none and HS256 without proper key rotation, and security header misalignment. BOLA and IDOR are identified through sequential ID enumeration and active adjacent-ID probing, while BFLA and privilege escalation are surfaced via admin endpoint probing and role/permission field leakage. The scanner also highlights Property Authorization risks like over-exposed internal fields and mass-assignment surfaces, and records Input Validation issues such as CORS wildcard usage with credentials, dangerous HTTP methods, and debug endpoints. Each finding includes context and remediation guidance tied to the relevant framework control.

The scanner parses OpenAPI 3.0, 3.1, and Swagger 2.0 documents with recursive $ref resolution, then cross-references spec definitions against runtime behavior to find undefined security schemes, sensitive fields, deprecated operations, and missing pagination. For authenticated scans, which require Starter tier or higher, middleBrick supports Bearer tokens, API keys, Basic auth, and Cookies. A domain verification gate ensures that only the domain owner can scan with credentials, validating ownership via DNS TXT record or an HTTP well-known file. The scanner strictly forwards a header allowlist limited to Authorization, X-API-Key, Cookie, and X-Custom-* headers to minimize credential exposure.

middleBrick includes a dedicated LLM / AI Security category with 18 adversarial probes 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, base64 and ROT13 encoding bypass, translation-embedded injection, few-shot poisoning, markdown injection, multi-turn manipulation, indirect prompt injection, token smuggling, tool-abuse, nested instruction injection, and PII extraction. Because these techniques rely on semantic manipulation rather than classic payloads, they are surfaced as distinct findings with model-specific risk descriptions. This coverage helps teams understand prompt-injection risk surfaces without relying on generic input validation checks.

Results are accessible via a Web Dashboard for scanning, trend tracking, and downloading branded compliance PDFs, and via a CLI provided as an npm package with JSON or text output. A GitHub Action can gate CI/CD, failing the build when the score drops below a configured threshold. The MCP Server enables scanning from AI coding assistants such as Claude and Cursor. Continuous monitoring in Pro tier supports scheduled rescans every 6 hours, daily, weekly, or monthly, with diff detection for new findings, resolved findings, and score drift. Email alerts are rate-limited to 1 per hour per API, and webhooks are HMAC-SHA256 signed, with auto-disable after 5 consecutive failures. Customer data is deletable on demand and purged within 30 days of cancellation; it is never sold or used for model training.