CVE-2026-39964
A bot author can set a link URL to javascript:PAYLOAD, which executes in the visitor's browser context when clicked.
Does this matter?
Lower severity and a low EPSS score (0.24%). Track it; it rarely justifies an emergency change on its own.
Description
TypeBot is a chatbot builder tool. In versions prior to 3.16.0, the Typebot viewer (packages/embeds/js) renders anchor tags from rich text bubble content without filtering the javascript: URI scheme. A bot author can set a link URL to javascript:PAYLOAD, which executes in the visitor's browser context when clicked. Since the viewer is typically embedded in a third-party site, the attacker's JavaScript runs in the host page's origin and can exfiltrate cookies and session tokens. This can result in any authenticated Typebot user (including those on the free tier) being able to create a bot with this payload. Shared bots are publicly accessible — no victim authentication is required. This issue has been resolved in version 3.16.0.
- CVSS 3.1
- 5.4 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 0.24% probability · 15th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Source
- security-advisories@github.com
References
- https://github.com/baptisteArno/typebot.io/commit/2c3fc7267a5e1529ba4b1a2ab4f1edb3e3b8990b
- https://github.com/baptisteArno/typebot.io/releases/tag/v3.16.0
- https://github.com/baptisteArno/typebot.io/security/advisories/GHSA-hqmv-v56g-4m47
- https://github.com/baptisteArno/typebot.io/security/advisories/GHSA-hqmv-v56g-4m47
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.