Typebot.io versions 3.15.2 and earlier contain a cross-site scripting vulnerability (CWE-79) in the RatingButton component of the embed package. This component directly injects user-controlled customIcon.svg content into the DOM using Solid's innerHTML directive without sanitization, even though DOMPurify is available and used elsewhere. Because rating blocks are not marked as unsafe by the import sanitizer and the builder preview runs inline on builder.typebot.io with a Content Security Policy allowing 'unsafe-inline', an attacker can execute arbitrary HTML/JavaScript in the authenticated builder context. This bypasses the Web Worker sandbox that normally protects script blocks during preview, enabling session hijacking and privilege escalation. The vulnerability is resolved in version 3.16.0.

Successful exploitation allows an attacker to execute arbitrary HTML and JavaScript in the authenticated context of the typebot.io builder application. This can lead to session hijacking and privilege escalation, compromising the security of the builder environment. There is no indication of impact on availability. No known exploits are reported in the wild at this time.

This vulnerability has been fixed in typebot.io version 3.16.0. Users and administrators should upgrade to version 3.16.0 or later to remediate this issue. Patch status is not explicitly stated beyond the fix in 3.16.0, so verify with the vendor advisory for the latest remediation guidance.