Fireblocks Webhooks

When to Use This Skill

• How do I receive Fireblocks webhooks?
• How do I verify the Fireblocks-Webhook-Signature header?
• Why is my Fireblocks webhook signature verification failing?
• How do I handle transaction.created or transaction.status.updated events?
• How do I validate a Fireblocks detached JWS (RS512) against the JWKS endpoint?

Verification (core)

Fireblocks Webhooks v2 signs every request with a detached JWS (RS512, RSA + SHA-512) in the Fireblocks-Webhook-Signature header. The header is a compact JWS with an empty payload segment (<protected-header>..<signature>). To verify, reinsert the raw request body (base64url-encoded) as the payload, then verify against the auto-rotated regional JWKS (https://keys.fireblocks.io/.well-known/jwks.json). Use the raw body bytes — never JSON.parse first.

import { createRemoteJWKSet, compactVerify } from 'jose';