Payment status is trusted only after server-side verification.

Core controls

FormXpert Pay does not treat a browser redirect, screenshot or manually entered UTR as proof of payment. Final success is based on the provider's server response and exact order amount.

• HMAC-SHA256 API signatures with timestamp + nonce
• Replay protection and per-minute rate limiting
• Unique Paytm transaction ID constraint
• Database row lock before final payment transition
• Idempotency-Key protection for order creation
• AES-256-GCM encryption for merchant secrets at rest
• Signed outgoing webhooks and retry logs
• HTTPS-only merchant return/webhook URLs