CVE-2020-35480: Debian Linux

Medium severity, CVSS 5.3. EPSS: 1.5% chance of exploitation in the next 30 days.

An issue was discovered in MediaWiki before 1.35.1. Missing users (accounts that don't exist) and hidden users (accounts that have been explicitly hidden due to being abusive, or similar) that the viewer cannot see are handled differently, exposing sensitive information about the hidden status to unprivileged viewers. This exists on various code paths.

Affected products

• Debian Debian Linux: version 9.0 only; version 10.0 only
• Fedoraproject Fedora: version 33 only
• Mediawiki Mediawiki: before 1.35.1 (fixed in 1.35.1)

Published 2020-12-18. Last modified 2026-06-17.