APIsec for Webhook senders

Webhook senders initiate outbound calls to third-party endpoints, often with user-controlled or event-driven payloads. This surface can expose integration logic, authentication material, and sensitive data if requests are malformed or intercepted. The scanner evaluates the sender-facing API surface and related endpoints without accessing your code or runtime. Findings are mapped to OWASP API Top 10 (2023) and aligned with security controls described in PCI-DSS 4.0 and SOC 2 Type II.

The scanner assesses webhook senders using read-only methods (GET and HEAD) and text-only POST for LLM probes. It checks for insecure transport, authentication leaks, and data exposure in webhook configuration and callback URLs. Specific coverage includes:

• Authentication bypass risks around webhook secret validation and token handling.
• Data exposure through error messages, PII in payloads, and API key leakage in logs or headers.
• Input validation gaps such as CORS wildcard usage, unsafe HTTP methods, and unverified redirects.
• Server-side request forgery potential when URL-accepting parameters point to internal services.
• Rate limiting and resource consumption indicators that could lead to denial conditions.

Unsupported detections include active SQL injection, command injection, and blind SSRF, which fall outside the scanner’s read-only scope.

Authenticated scans (Starter tier and above) allow the tool to validate webhook sender configurations using Bearer tokens, API keys, Basic auth, or cookies. Domain verification is enforced through DNS TXT records or an HTTP well-known file to ensure only the domain owner can submit credentials. The scanner forwards a restricted set of headers and does not execute destructive payloads. This approach helps surface issues such as over-exposed internal fields, missing versioning, and misconfigured security schemes without impacting production systems.

Webhook senders that incorporate LLM interactions or AI tooling are subject to adversarial probing across three scan tiers: Quick, Standard, and Deep. These probes test for system prompt extraction, instruction override attempts, and data exfiltration paths that could abuse webhook-driven AI features. The scanner also checks for base64 or ROT13 encoding bypasses, prompt injection patterns, token smuggling, and multi-turn manipulation risks. Findings are reported with remediation guidance, and this testing does not involve active exploits or destructive actions.

Scanner output provides prioritized findings and references remediation steps, but it does not automatically fix, patch, or block issues. Teams should treat results as audit evidence and use them to guide manual review and secure coding practices. Pro tier continuous monitoring can schedule periodic rescans, track score drift, and deliver diff-based alerts via email or HMAC-SHA256 signed webhooks. This helps maintain a consistent security posture for evolving webhook sender integrations.