Alternatives to 42Crunch for Bug bounty triage assist

When validating external attack surfaces, teams need a fast way to separate low-risk noise from material findings that merit deeper investigation. This tool is a black-box API scanner designed to support that triage step. You submit a target URL and receive a risk score on an A to F scale, with prioritized findings mapped to three frameworks: PCI-DSS 4.0, SOC 2 Type II, and OWASP API Top 10 (2023). The scan runs in under a minute using only read-only methods (GET and HEAD) plus text-only POST for LLM probes, which means it does not modify, block, or remediate anything.

The scanner covers 12 categories aligned to OWASP API Top 10 (2023), including authentication bypasses, JWT misconfigurations such as alg=none or expired tokens, BOLA and IDOR via sequential ID probing, BFLA and privilege escalation indicators, over-exposed properties and mass-assignment surfaces, input validation issues like CORS wildcard usage and dangerous HTTP methods, rate-limiting signals and oversized responses, data exposure patterns including emails, Luhn-validated card numbers, context-aware SSNs, and API key formats for AWS, Stripe, GitHub, and Slack. It also detects HTTPS redirect issues, HSTS and cookie flags, SSRF indicators involving URL-accepting parameters and internal IP probes, missing API versioning and legacy paths, unsafe consumption surfaces, and LLM security probes across Quick, Standard, and Deep tiers.

• System prompt extraction and instruction override attempts.
• DAN and roleplay jailbreaks alongside data exfiltration indicators.
• Cost exploitation, base64 or ROT13 encoding bypasses, and token smuggling.

Because the scanner is read-only, it does not perform active SQL injection or command injection tests, does not detect blind SSRF requiring out-of-band infrastructure, and does not identify business logic flaws that require domain-specific human analysis. It is not a replacement for a human pentester in high-stakes audit scenarios.

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. This highlights undefined security schemes, sensitive fields in responses, deprecated operations, and missing pagination that may indicate enumeration risks. For authenticated scans, which require the Starter tier or higher, you can provide Bearer tokens, API keys, Basic auth, or cookies. Before scanning with credentials, the platform verifies domain ownership through a DNS TXT record or an HTTP well-known file, ensuring only the domain owner can run authenticated checks. Header forwarding is limited to Authorization, X-API-Key, Cookie, and X-Custom-* headers to reduce noise.

The platform provides several interfaces for different workflows. The Web Dashboard centralizes scans, report viewing, score trend tracking, and downloadable compliance PDFs. The CLI, published as an npm package named middlebrick, supports commands such as middlebrick scan https://api.example.com with JSON or text output. A GitHub Action can gate CI/CD pipelines, failing the build when the score drops below a configured threshold. An MCP Server allows scanning from AI coding assistants like Claude or Cursor, and a programmable API supports custom integrations. Continuous monitoring in the Pro tier enables rescans on 6-hour, daily, weekly, or monthly schedules, with diff detection for new findings, resolved issues, and score drift. Email alerts are rate-limited to one per hour per API, and webhooks are HMAC-SHA256 signed, with auto-disable after five consecutive failures.

Scan data is deletable on demand and purged within 30 days of cancellation. Customer data is never sold and is not used for model training. The scanner employs layered protections against internal, localhost, and cloud metadata endpoints, and it only uses read-only methods, ensuring no destructive payloads are transmitted. These characteristics make it suitable for recurring checks without introducing operational risk.

Pricing tiers are as follows: Free at $0 per month for 3 scans; Starter at $99 per month for 15 APIs with monthly scans, dashboard access, email alerts, and the MCP Server; Pro at $499 per month for 100 APIs plus $7 per additional API, adding continuous monitoring, GitHub Action gates, CI/CD integration, Slack or Teams alerts, compliance reports, and signed webhooks; Enterprise at $2000 per month for unlimited APIs, custom rules, SSO, audit logs, SLA, and dedicated support.