An issue was discovered in the CheckUser extension for MediaWiki through 1.42.1. The API can expose suppressed information for log events. (The log_deleted attribute is not applied to entries.)
Information written to log files can be of a sensitive nature and give valuable guidance to an attacker or expose sensitive user information.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Mediawiki | Mediawiki | * | 1.42.1 (including) |
While logging all information may be helpful during development stages, it is important that logging levels be set appropriately before a product ships so that sensitive user data and system information are not accidentally exposed to potential attackers. Different log files may be produced and stored for: