In Typebot versions 3.15.2 and earlier, the preview chat endpoint accepts a custom typebot definition that can include server‑side code blocks. The fetch function executed inside an isolated‑VM sandbox calls Node.js native fetch, bypassing the SSRF validation used by the HTTP Request block. This flaw is classified as a Server‑Side Request Forgery and is identified by CWE-918 and CWE‑862. Exploiting the vulnerability allows an unauthenticated user to make arbitrary outbound HTTP requests, potentially leaking cloud credentials, gaining internal network access, or exfiltrating sensitive data.

The affected product is Typebot, developed by baptisteArno. Any self‑hosted or hosted deployment running version 3.15.2 or earlier is vulnerable; the issue is resolved in version 3.16.0.

The CVSS score for this flaw is 10, indicating critical severity. No EPSS score is publicly available, but the absence of a KEV listing does not reduce the potential impact. The attack path requires no special credentials and only an unauthenticated POST to the preview chat endpoint, making the vulnerability highly exploitable in cloud and internal environments.