CVE-2020-25812

Name: CVE-2020-25812
Creator: NVD / NIST
Published: 2020-09-27T21:15:12.563+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 1.10%

Last modified Jun 17, 2026

CVE-2020-25812 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. 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. EPSS estimates a 1.10% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

6.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

EPSS Probability

1.10%

61.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Mediawiki	Mediawiki	>= 1.34.0, < 1.34.4
Fedoraproject	Fedora	33

References

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

Timeline

Published: Sep 27, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-25812?

How severe is CVE-2020-25812?

CVE-2020-25812 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 1.10% probability of exploitation in the next 30 days.

How do I fix CVE-2020-25812?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-25812?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST