CVE-2026-47099 TeleJSON < 6.0.0 DOM-based XSS via parse() Function
Attackers can execute arbitrary JavaScript via crafted JSON payloads in TeleJSON, impacting applications using this library for parsing.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-47099?
CVE-2026-47099 is a low-severity cross-site scripting vulnerability in storybookjs telejson, published on 20 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
TeleJSON prior to 6.0.0 contains a DOM-based cross-site scripting vulnerability in the parse() function that allows attackers to execute arbitrary JavaScript by delivering a crafted JSON payload containing a malicious _constructor-name_ property value. The custom reviver passes the constructor name directly to new Function() without sanitization when recreating object prototypes, enabling attackers to inject arbitrary JavaScript through vectors such as postMessage in cross-frame communication contexts to achieve script execution within the application.
Weakness: CWE-79
Which versions are affected by CVE-2026-47099?
2 open source packages ship an affected version, including telejson.
| Package | Affected | Fixed in |
|---|---|---|
telejson npm | All versions | 6.0.0 |
telejson npm | All versions | 6.0.0 |
How do I fix CVE-2026-47099?
Upgrade telejson to 6.0.0 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-47099 being exploited?
There is no known exploitation of CVE-2026-47099 in the wild and no public exploit code.
Sources
Also known as GHSA-ccgf-5rwj-j3hv.