CVE-2025-66648 `vega-functions` vulnerable to Cross-site Scripting via `setdata` function
Attackers can execute arbitrary JavaScript via the setdata function in vega-functions, affecting sites processing untrusted user input.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-66648?
CVE-2025-66648 is a high-severity cross-site scripting vulnerability in vega, published on 5 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
vega-functions provides function implementations for the Vega expression language. Prior to version 6.1.1, for sites that allow users to supply untrusted user input, malicious use of an internal function (not part of the public API) could be used to run unintentional javascript (XSS). This issue is fixed in vega-functions `6.1.1`. There is no workaround besides upgrading. Using `vega.expressionInterpreter` as described in CSP safe mode does not prevent this issue.
Weakness: CWE-79
Which versions are affected by CVE-2025-66648?
2 open source packages ship an affected version, including vega-functions. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
vega-functions npm | All versions | 6.1.1 |
vega-functions npm | All versions | 6.1.1 |
Products include Vega-Functions Project Vega-Functions.
How do I fix CVE-2025-66648?
Upgrade vega-functions to 6.1.1 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-2025-66648 being exploited?
There is no known exploitation of CVE-2025-66648 in the wild and no public exploit code.
Other vulnerabilities in vega
Sources
Also known as DEBIAN-CVE-2025-66648, GHSA-m9rg-mr6g-75gm, UBUNTU-CVE-2025-66648.