MediaWiki checkuser extension for Media wiki any version

Wrong E-Mail address composition for usernames with a comma and Umlauts in it like "Döe, Jähn"

Suggested investigations: Handle suppressed usernames

Cross-site request forgery (CSRF) vulnerability in the CheckUser extension for MediaWiki allows remote attackers to hijack the authentication of certain users for requests that retrieve sensitive user information via unspecified vectors.

An issue was discovered in the CheckUser extension through 1.34 for MediaWiki. Certain sensitive information within oversighted edit summaries made available via the MediaWiki API was potentially visible to users with various levels of access to this extension. Said users should not have been able to view these oversighted edit summaries via the MediaWiki API.

i18n XSS through Special:CheckUser CheckUser helper

Stored XSS through system messages in CheckUser

An issue was discovered in the CheckUser extension through 1.35.0 for MediaWiki. Oversighted edit summaries are still visible in CheckUser results in violation of MediaWiki's permissions model.

Special:GlobalContributions shows edits on wikis the viewer doesn't have access to