Related Vulnerabilities: CVE-2020-35479  

MediaWiki before 1.35.1 allows XSS via BlockLogFormatter.php. Language::translateBlockExpiry itself does not escape in all code paths. For example, the return of Language::userTimeAndDate is is always unsafe for HTML in a month value. This affects MediaWiki 1.12.0 and later.

Severity Medium

Remote Yes

Type Cross-site scripting

Description

MediaWiki before 1.35.1 allows XSS via BlockLogFormatter.php. Language::translateBlockExpiry itself does not escape in all code paths. For example, the return of Language::userTimeAndDate is is always unsafe for HTML in a month value. This affects MediaWiki 1.12.0 and later.

AVG-1371 mediawiki 1.35.0-1 1.35.1-1 Medium Fixed FS#69132

https://phabricator.wikimedia.org/T268938
https://github.com/wikimedia/mediawiki/commit/78663c50df6b953f4c832e1530515ebe91e1eb5d