base element unsafe in default sanitizer configuration#44697
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(comment last updated: 2026-07-13 01:42:36) |
hamishwillee
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LGTM; thanks, @hamishwillee!
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Fixes #44673
The
<base>element is now explicitly marked as unsafe in whatwg/html#12664 (rather than "uncategorized"). This updates the https://developer.mozilla.org/en-US/docs/Web/API/HTML_Sanitizer_API/Default_sanitizer_configuration list to add it to the list of explicitly unsafe elements.I also noted that some elements are removed by default because they are deprecated, not necessarily attack vectors. This is the case for elements like
<acronym>.The actual default configuration has not changed, since base was already omitted as a potential attack.
I also updated
Sanitizer/removeUnsafe()with the needed change, but we shouldn't merge this until the BCD goes in