What is CVE-2025-62410?

CVE-2025-62410 is a vulnerability in Capricorn86 Happy-Dom, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). Published 2025-10-15.

Is CVE-2025-62410 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Prototype Pollution in Capricorn86 Happy-Dom

CVE-2025-62410

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.

Vulnerability class: Prototype Pollution

EPSS: 0.003 (25.0th percentile) — read the EPSS interpretation.

Affected products

Capricorn86 Happy-dom — versions < 20.0.2

Weakness classification (CWE)

CWE-1321 — Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution)

Public proof-of-concept exploits

fkie-cad/nvd-json-data-feeds

References

security-advisories@github.com (x_refsource_CONFIRM)
security-advisories@github.com (x_refsource_MISC)

Frequently asked questions

What is CVE-2025-62410?: CVE-2025-62410 is a vulnerability in Capricorn86 Happy-Dom, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). Published 2025-10-15.
Is CVE-2025-62410 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.