In MediaWiki through 1.37, XSS can occur in Wikibase because an external identifier property can have a URL format that includes a $1 formatter substitution marker, and the javascript: URL scheme (among others) can be used.
| Software | From | Fixed in |
|---|---|---|
| mediawiki / mediawiki | - | 1.37.x |
| fedoraproject / fedora | 35 | 35.x |