fix(multiple): harden extendStyles and trusted-types against prototype pollution and DOM clobbering#33410
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arturovt wants to merge 1 commit into
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fix(multiple): harden extendStyles and trusted-types against prototype pollution and DOM clobbering#33410arturovt wants to merge 1 commit into
arturovt wants to merge 1 commit into
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…e pollution and DOM clobbering Replace `source.hasOwnProperty(key)` with `Object.hasOwn(source, key)` in the two `extendStyles` helpers (drag-drop/styling and flexible-connected-position-strategy). Calling hasOwnProperty as an instance method is unsafe when Object.prototype itself has been polluted — Object.hasOwn has no such exposure. Wrap `trustedTypes.createPolicy()` in a try/catch in trusted-types.ts. The call can throw if window.trustedTypes was DOM-clobbered with an HTML element before Angular bootstrapped, which previously caused an unhandled exception and silently skipped policy creation. The catch falls back to null, preserving the existing DomSanitizer sanitization path in _setInnerHtml. Add "es2022.object" to the root tsconfig lib to make Object.hasOwn available; the target was already es2022 so this aligns the type surface without broadening it further.
crisbeto
reviewed
Jun 17, 2026
| // window.trustedTypes was DOM-clobbered with an HTML element before | ||
| // Angular bootstrapped. Either way, null means trustedHTMLFromString | ||
| // falls back to plain strings — sanitization in _setInnerHtml still runs. | ||
| policy = null; |
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This seems a bit pointless since the policy won't be created if there's an error.
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| /** Shallow-extends a stylesheet object with another stylesheet object. */ | ||
| function extendStyles( |
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We only call this internally with a pre-defined set of values so this isn't necessary.
| ) { | ||
| for (let key in source) { | ||
| if (source.hasOwnProperty(key)) { | ||
| if (Object.hasOwn(source, key)) { |
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We only call this internally with a pre-defined set of values so this isn't necessary.
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Replace
source.hasOwnProperty(key)withObject.hasOwn(source, key)in the twoextendStyleshelpers (drag-drop/styling and flexible-connected-position-strategy). Calling hasOwnProperty as an instance method is unsafe when Object.prototype itself has been polluted — Object.hasOwn has no such exposure.Wrap
trustedTypes.createPolicy()in a try/catch in trusted-types.ts. The call can throw if window.trustedTypes was DOM-clobbered with an HTML element before Angular bootstrapped, which previously caused an unhandled exception and silently skipped policy creation. The catch falls back to null, preserving the existing DomSanitizer sanitization path in _setInnerHtml.Add "es2022.object" to the root tsconfig lib to make Object.hasOwn available; the target was already es2022 so this aligns the type surface without broadening it further.