Description
happy-dom v20.8.9 makes real server-side HTTP requests to arbitrary URLs when parsing HTML containing <iframe> or <link rel="stylesheet"> elements. This behavior is enabled by default (disableIframePageLoading: false, disableCSSFileLoading: false).
Recommendation
Update the happy-dom package to the latest compatible version. Followings are version details:
- Affected version(s): <= 20.14.6
- Patched version(s): 21.0.0
References
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Start a free scanRelated Issues
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- Happy DOM: Incomplete fix for CVE-2026-33943: unsanitized import alias leads to host code execution - CVE-2026-115895
- ApostropheCMS sanitize-html: unbounded recursion when re-sanitizing the fallback of a discarded iframe (stack overflow, - CVE-2026-113650
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See something that needs correcting? Let us knowUpdated October 28, 2026