An issue was discovered in the Phonos extension in MediaWiki before 1.40.2. PhonosButton.js allows i18n-based XSS via the phonos-purge-needed-error message.Referenceshttps://lists.wikimedia.org/hyperkitty/list/mediawiki-announce%40lists.wikimedia.org/message/TDBUBCCOQJUT4SCHJNPHKQNPBUUETY52/https://phabricator.wikimedia.org/T349312