> For the complete documentation index, see [llms.txt](https://docs.xaman.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.xaman.dev/concepts/payloads-sign-requests/status-updates/webhooks/signature-verification.md).

# Signature verification

Signature verification is crucial for ensuring the integrity and authenticity of the data received. It involves verifying that the data was sent by Xumm and has not been tampered with.

If you want to make sure a WebHook received by your platform has been sent by the Xumm platform, verify the signature the platform sends in an HTTP header.

Every WebHook call contains a signature to verify the authenticity. It sends an HMAC using your application secret as a key. Sample verification in NodeJS:

```javascript
import crypto from 'crypto'

// Xumm App secret (Xumm developer console)
const secret = 'xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx'

const timestamp = req.headers?.['x-xumm-request-timestamp'] || ''
const json = req.body

const hmac = crypto.createHmac('sha1', secret.replace('-', ''))
  .update(timestamp + JSON.stringify(json))
  .digest('hex')

console.log(hmac, hmac === req.headers?.['x-xumm-request-signature'])
```


---

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