What’s Vulnerable › Vulnerabilities

CVE-2020-25812

• Severity: medium (CVSS 6.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-09-27 · updated 2026-06-17
• Weakness: CWE-79

Description

An issue was discovered in MediaWiki 1.34.x before 1.34.4. On Special:Contributions, the NS filter uses unescaped messages as keys in the option key for an HTMLForm specifier. This is vulnerable to a mild XSS if one of those messages is changed to include raw HTML.

Affected products

• Fedoraproject Fedora: 33
• Wikimedia Foundation MediaWiki: from 1.34.0 before 1.34.4 — fixed in 1.34.4

How to fix

Upgrade to a fixed version: Wikimedia Foundation MediaWiki 1.34.4. Check the vendor advisory for mitigations.

References

• https://gerrit.wikimedia.org/g/mediawiki/core/+/ad4a3ba45fb955aa8c0eb3c83809b16b40a498b9/includes/specials/SpecialContributions.php#592
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RTTPZ7XMDS66I442OLLHXBDNP2LCBJU6/
• https://lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048480.html
• https://lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048488.html
• https://gerrit.wikimedia.org/g/mediawiki/core/+/ad4a3ba45fb955aa8c0eb3c83809b16b40a498b9/includes/specials/SpecialContributions.php#592
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RTTPZ7XMDS66I442OLLHXBDNP2LCBJU6/
• https://lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048480.html
• https://lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048488.html

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