CVE-2026-39964
TypeBot: Stored XSS via javascript: URI in text bubble links — bot author executes JS on visitors' browsers
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.
INFO
Published Date :
May 22, 2026, 6:16 p.m.
Last Modified :
May 23, 2026, 4:16 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update Typebot to version 3.16.0 or later.
- Ensure rich text content is properly sanitized.
- Review and sanitize all external link inputs.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-39964.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-39964 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-39964
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
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The following list is the news that have been mention
CVE-2026-39964 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-39964 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
May. 23, 2026
Action Type Old Value New Value Added Reference https://github.com/baptisteArno/typebot.io/security/advisories/GHSA-hqmv-v56g-4m47 -
New CVE Received by [email protected]
May. 22, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Added CWE CWE-79 Added Reference https://github.com/baptisteArno/typebot.io/commit/2c3fc7267a5e1529ba4b1a2ab4f1edb3e3b8990b Added Reference https://github.com/baptisteArno/typebot.io/releases/tag/v3.16.0 Added Reference https://github.com/baptisteArno/typebot.io/security/advisories/GHSA-hqmv-v56g-4m47