CVE-2026-28445: Typebot is a chatbot builder tool. In versions 3.15.2 and prior, the RatingButton component in the embed package renders the user-controlled customIco...

Description

Typebot is a chatbot builder tool. In versions 3.15.2 and prior, the RatingButton component in the embed package renders the user-controlled customIcon.svg field directly via Solid's innerHTML directive without any sanitization, even though DOMPurify is already a dependency and is used elsewhere in the codebase (e.g., StreamingBubble.tsx). Because rating blocks are not flagged as isUnsafe by the import sanitizer and the builder preview renders bots inline on the builder's own origin (builder.typebot.io) under a CSP permitting 'unsafe-inline', a malicious imported or collaborator-crafted typebot can execute arbitrary HTML/JS in the builder's authenticated context, bypassing the Web Worker sandbox that protects Script blocks during preview. This allows session hijacking and privilege escalation within the builder application. This issue has been fixed in version 3.16.0.

Metrics

CVSS 3.1

8.7/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N

EPSS Probability

0.26%

16.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

References

Timeline

Published: May 22, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-28445?

Typebot is a chatbot builder tool. In versions 3.15.2 and prior, the RatingButton component in the embed package renders the user-controlled customIcon.svg field directly via Solid's innerHTML directive without any sanitization, even though DOMPurify is already a dependency and is used elsewhere in the codebase (e.g., StreamingBubble.tsx). Because rating blocks are not flagged as isUnsafe by the import sanitizer and the builder preview renders bots inline on the builder's own origin (builder.typebot.io) under a CSP permitting 'unsafe-inline', a malicious imported or collaborator-crafted typebot can execute arbitrary HTML/JS in the builder's authenticated context, bypassing the Web Worker sandbox that protects Script blocks during preview. This allows session hijacking and privilege escalation within the builder application. This issue has been fixed in version 3.16.0.

How severe is CVE-2026-28445?

CVE-2026-28445 has a CVSS score of 8.7/10 (HIGH severity). The EPSS model estimates a 0.26% probability of exploitation in the next 30 days.

How do I fix CVE-2026-28445?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.