Element.setHTML(): add mXSS warning about re-parsing sanitized HTML#43990
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(comment last updated: 2026-06-05 05:29:07) |
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Hello, could you please review the above changes mentioned. |
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Co-authored-by: Hamish Willee <hamishwillee@gmail.com>
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Thanks very much for adding this @narasimhan-lakshmi
I have somewhat re-written this to better match MDN conventions and to improve readability. In particular I wanted to make it clear that the problem here is ever using innerHTML or injecting HTML wihtout a sanitization path.
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Description
Re-parsing and mutated XSS (mXSS) security section explaining innerHTML round-trip risk, example unsafe flow, mitigation recommendations along with reference
Motivation
Make readers to avoid risk and stay updatedAdditional details
Related issues and pull requests
Fixes #43386