[MEDIUM] Special:UserRights exposes the existence of hidden users

PKSA-d4kb-dkjp-1n1j CVE-2020-25813 GHSA-c4rj-wrmq-52rj

Affected package: mediawiki/core

Affected version: >=1.31.0,<1.31.9|>=1.34.0,<1.34.3

Reported by:
GitHub, FriendsOfPHP/security-advisories