5.4
MEDIUM CVSS 3.1
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, 5:21 p.m.

Last Modified :

May 22, 2026, 5:21 p.m.

Remotely Exploit :

Yes !

Source :

GitHub_M
Affected Products

The following products are affected by CVE-2026-39964 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM MITRE-CVE
Solution
Update Typebot viewer to version 3.16.0 or later to fix JavaScript execution from rich text links.
  • Update Typebot to version 3.16.0 or later.
  • Ensure rich text content is properly sanitized.
  • Review and sanitize all external link inputs.

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).

Results are limited to the first 15 repositories due to potential performance issues.

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.

  • 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
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.