RCE in Capricorn86 Happy-Dom

CVE-2025-61927

Happy DOM is a JavaScript implementation of a web browser without its graphical user interface. Happy DOM v19 and lower contains a security vulnerability that puts the owner system at the risk of RCE (Remote Code Execution) attacks. A Node.js VM Context is not an isolated environment, and if the user runs untrusted JavaScript code within the Happy DOM VM Context, it may escape the VM and get access to process level functionality. It seems like what the attacker can get control over depends on if the process is using ESM or CommonJS. With CommonJS the attacker can get hold of the `require()` function to import modules. Happy DOM has JavaScript evaluation enabled by default. This may not be obvious to the consumer of Happy DOM and can potentially put the user at risk if untrusted code is executed within the environment. Version 20.0.0 patches the issue by changing JavaScript evaluation to be disabled by default.

Vulnerability class: RCE (Remote Code Execution)

Published · last modified .

EPSS exploit prediction

EPSS: 0.006 (48.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 48.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-61927: held from 0.006 to 0.006.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: +0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-61927?
CVE-2025-61927 is a vulnerability in Capricorn86 Happy-Dom, classified under Code Injection. Published 2025-10-10.
Is CVE-2025-61927 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.