fix(core): prevent prototype pollution via jsaction attribute parsing#69159
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arturovt wants to merge 1 commit into
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fix(core): prevent prototype pollution via jsaction attribute parsing#69159arturovt wants to merge 1 commit into
arturovt wants to merge 1 commit into
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The `jsaction` attribute parser in `parseActions` previously stored event-action mappings in a plain object (`{}`) and used event type strings from DOM attributes directly as property keys. This meant that specially crafted event names such as `__proto__`, `constructor`, or `prototype` could interact with the object's prototype chain rather than behaving as ordinary data keys.
The module-level `parseCache` had a similar issue. It was also implemented as a plain object keyed by the raw `jsaction` attribute value, allowing special property names to collide with built-in object properties.
This change hardens both code paths by:
* Replacing `actionMap = {}` with `Object.create(null)`, creating an object with no prototype chain.
* Replacing `parseCache = {}` with `Object.create(null)` for the same reason.
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The
jsactionattribute parser inparseActionspreviously stored event-action mappings in a plain object ({}) and used event type strings from DOM attributes directly as property keys. This meant that specially crafted event names such as__proto__,constructor, orprototypecould interact with the object's prototype chain rather than behaving as ordinary data keys.The module-level
parseCachehad a similar issue. It was also implemented as a plain object keyed by the rawjsactionattribute value, allowing special property names to collide with built-in object properties.This change hardens both code paths by:
actionMap = {}withObject.create(null), creating an object with no prototype chain.parseCache = {}withObject.create(null)for the same reason.