APIsec for Webhook receivers
What middleBrick covers
- Black-box scanning of webhook receiver endpoints
- Authentication support for Bearer, API key, Basic, and Cookie
- Domain verification gate for credentialed scans
- Mapping findings to PCI-DSS, SOC 2, and OWASP API Top 10
- CI/CD integration via GitHub Action and MCP Server
- Prioritized findings with remediation guidance
Webhook receiver security overview
Webhook receivers accept inbound HTTP callbacks that often originate from third-party services. These endpoints are frequently less constrained than internal APIs, with relaxed schema expectations and varied authentication practices. Attack surface includes forged callbacks, parameter tampering, and unsafe deserialization when payloads are processed by downstream systems.
How middleBrick evaluates webhook receivers
middleBrick scans webhook receivers as black-box endpoints using read-only methods (GET, HEAD, and text-only POST for LLM probes). It inspects DNS ownership via domain verification, supports Bearer, API key, Basic auth, and Cookie authentication where permitted, and only forwards a limited allowlist of headers. The scanner checks the receiver surface for common misconfigurations and validates security-related headers and HTTPS properties that affect callback integrity.
Detection coverage aligned to compliance frameworks
middleBrick maps findings to PCI-DSS 4.0, SOC 2 Type II, and OWASP API Top 10 (2023) for webhook receiver assessments. It surfaces findings relevant to audit evidence for these frameworks, including checks for weak authentication, exposed sensitive data, and security header issues. The scanner also helps you prepare for controls around input validation, transport encryption, and error handling in callback processing paths.
Limitations and complementary practices
middleBrick does not detect business logic vulnerabilities inherent to webhook processing, such as replay attacks or idempotency bypass, which require domain-specific understanding. It does not perform active SQL injection or command injection testing, and it cannot identify blind SSRF that depends on out-of-band infrastructure. The scanner does not replace a human pentester for high-stakes audits of webhook receivers handling sensitive event streams.
Integration into webhook workflows
Use the CLI to run scans against receiver URLs: middlebrick scan https://api.example.com/webhook. Integrate the GitHub Action as a CI/CD gate to block merges when the score drops below your chosen threshold, or deploy the MCP Server to assess receiver configurations from AI-assisted development environments. The Web Dashboard centralizes results, tracks score trends, and generates branded compliance PDFs for documentation.