Vulnerability library
Security checkMarch 06, 2026

Vercel Workflow Allows Webhook Creation with Predictable User-Specified Tokens

Understand the exposure, see the recommended fix, and check whether your own website has related weaknesses.

Medium severitynpm@workflow/core

Check your website

Find this and other vulnerabilities with a free scan.

Your scan runs on your computer. No account required.

Description

createWebhook() in Vercel Workflow DevKit accepts a user-specified token parameter that serves as the credential for the public webhook endpoint /.well-known/workflow/v1/webhook/{token}.

Recommendation

Update the @workflow/core package to the latest compatible version. Followings are version details:

  • Affected version(s): <= 4.1.0-beta.63
  • Patched version(s): 4.2.0-beta.64

References

Could your website be exposed too?

SmartScanner can check your website for Vercel Workflow Allows Webhook Creation with Predictable User-Specified Tokens and gives you actionable findings to investigate.

Start a free scan

Related Issues

See something that needs correcting? Let us knowUpdated March 06, 2026