An issue was discovered in the SportsTeams extension for MediaWiki before 1.35.12, 1.36.x through 1.39.x before 1.39.5, and 1.40.x before 1.40.1. It does not check for the anti-CSRF edit token in Special:SportsTeamsManager and Special:UpdateFavoriteTeams.
https://phabricator.wikimedia.org/T345040
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/SportsTeams/+/952552/