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vulnerability

MediaWiki: CVE-2021-31553: Unquoted Search Path or Element

Severity
6
CVSS
(AV:N/AC:L/Au:N/C:N/I:P/A:P)
Published
Apr 22, 2021
Added
Apr 26, 2021
Modified
May 6, 2026

Description

An issue was discovered in the CheckUser extension for MediaWiki through 1.35.2. MediaWiki usernames with trailing whitespace could be stored in the cu_log database table such that denial of service occurred for certain CheckUser extension pages and functionality. For example, the attacker could turn off Special:CheckUserLog and thus interfere with usage tracking.

Solution

mediawiki-upgrade-latest

References

    Title
    Rapid7 Labs

    2026 Global Threat Landscape Report

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