CVE-2025-53478mediumCWE-79

CVE-2025-53478: medium-severity vulnerability in Wikimedia Foundation Mediawiki - CheckUser…

CheckUser: Reflected Cross-Site Scripting (XSS) in Special:Investigate via unsanitized i18n messages

Published

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 5.4epss 0.2%
The CheckUser extension’s Special:Investigate interface is vulnerable to reflected XSS due to improper escaping of certain internationalized system messages rendered on the “IPs and User agents” tab. This issue affects Mediawiki - CheckUser extension: from 1.39.X before 1.39.13, from 1.42.X before 1.42.7, from 1.43.X before 1.43.2.
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Affected products
Wikimedia Foundation · Mediawiki - CheckUser extension
Related CVEs — Wikimedia Foundation Mediawiki - CheckUser…

In the same product, most dangerous first.

CVE-2025-53479MEDIUMCheckUser: Reflected Cross-Site Scripting (XSS) in Special:CheckUser via unsanitized internationalized messageEPSS 0.2%CVE-2025-53480MEDIUMCheckUser: Reflected Cross-Site Scripting (XSS) in Special:Investigate (Account information tab) via unsanitized i18n messagesEPSS 0.2%