The vulnerability allows a bot author to embed a link that uses the javascript: URI scheme within a rich text bubble. When a user clicks the link in the viewer, the browser executes the supplied JavaScript in the context of the host page, which can access and exfiltrate cookies or session tokens and leak user data. This constitutes a stored cross‑site scripting flaw that can compromise confidentiality and data integrity for anyone who views the affected bot.

The flaw exists in Typebot.io (baptisteArno) versions earlier than 3.16.0. Any user of the platform who can create or edit bots—including free tier accounts—can embed the malicious link, and all visitors to a shared or public bot are potential victims.

The CVSS score of 5.4 indicates a moderate severity. The EPSS score is currently unavailable, which suggests the exploit likelihood is unknown, and the vulnerability is not listed in the CISA KEV catalog. Attackers must have the ability to build or modify a bot and need users to click the injected link on a page that embeds the Typebot viewer. Once triggered, the attacker’s script runs as if it originated from the host site, providing significant risk to data confidentiality for all visitors.