CVE-2020-35474

Name: CVE-2020-35474
Creator: NVD / NIST
Published: 2020-12-18T08:15:15.06+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 1.03%

Last modified Jun 17, 2026

CVE-2020-35474 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. In MediaWiki before 1.35.1, the combination of Html::rawElement and Message::text leads to XSS because the definition of MediaWiki:recentchanges-legend-watchlistexpiry can be changed onwiki so that the output is raw HTML.. EPSS estimates a 1.03% chance of exploitation in the next 30 days.

Description

In MediaWiki before 1.35.1, the combination of Html::rawElement and Message::text leads to XSS because the definition of MediaWiki:recentchanges-legend-watchlistexpiry can be changed onwiki so that the output is 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

1.03%

59.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Mediawiki	Mediawiki	< 1.35.1
Fedoraproject	Fedora	33

References

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/STT5Z4A3BCXVH3WIPICWU2FP4IPIMUPC/
https://lists.wikimedia.org/pipermail/mediawiki-announce/2020-December/000268.htmlMailing List, Release Notes, Vendor Advisory
https://phabricator.wikimedia.org/T268894Exploit, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/STT5Z4A3BCXVH3WIPICWU2FP4IPIMUPC/
https://lists.wikimedia.org/pipermail/mediawiki-announce/2020-December/000268.htmlMailing List, Release Notes, Vendor Advisory
https://phabricator.wikimedia.org/T268894Exploit, Third Party Advisory

Timeline

Published: Dec 18, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-35474?

How severe is CVE-2020-35474?

CVE-2020-35474 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 1.03% probability of exploitation in the next 30 days.

How do I fix CVE-2020-35474?

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-2020-35474?

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

Scan your code now

Source: NVD / NIST