An issue was discovered in the Mentor dashboard in the GrowthExperiments extension in MediaWiki through 1.36.2. The Growthexperiments-mentor-dashboard-mentee-overview-add-filter-total-edits-headline, growthexperiments-mentor-dashboard-mentee-overview-add-filter-starred-headline, growthexperiments-mentor-dashboard-mentee-overview-info-text, growthexperiments-mentor-dashboard-mentee-overview-info-legend-headline, and growthexperiments-mentor-dashboard-mentee-overview-active-ago MediaWiki messages were not being properly sanitized and allowed for the injection and execution of HTML and JavaScript.