CVE-2025-62410
Critical
Description
In versions before 20.0.2, it was found that --disallow-code-generation-from-strings is not sufficient for isolating untrusted JavaScript in happy-dom. The untrusted script and the rest of the application still run in the same Isolate/process, so attackers can deploy prototype pollution payloads to hijack important references like "process" in the example below, or to hijack control flow via flipping checks of undefined property. This vulnerability is due to an incomplete fix for CVE-2025-61927. The vulnerability is fixed in 20.0.2.
SeverityCritical
CVSS9.4
Exploit probability—
ProductHappy-dom
PublishedOct 15, 2025
First seenOct 15, 2025
Weakness typeCWE-1321Prototype pollution
How to fix
Update
- happy-dom20.0.2 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| happy-domnpm | 19.0.0 ≤ v < 20.0.2 | 20.0.2 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
In the Intelligence 360 plan
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.