MediaWiki Cross-site Scripting (XSS) vulnerability
An issue was discovered in MediaWiki before 1.31.9 and 1.32.x through 1.34.x before 1.34.3. The non-jqueryMsg version of mw.message().parse() doesn't escape HTML. This affects both message contents (which are generally safe) and the parameters (which can be based on user input). (When jqueryMsg is loaded, it correctly accepts only whitelisted tags in message contents, and escapes all parameters. Situations with an unloaded jqueryMsg are rare in practice, but can for example occur for Special:SpecialPages on a wiki with no extensions installed.)
Affected software
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| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Composer package | mediawiki/core | >= 1.31.0, < 1.31.9, >= 1.32.0, < 1.34.3, >= 1.35.0-rc.0, < 1.35.0 | 1.31.9, 1.34.3, 1.35.0 |
References
- https://nvd.nist.gov/vuln/detail/CVE-2020-25828
- https://github.com/FriendsOfPHP/security-advisories/blob/master/mediawiki/core/CVE-2020-25828.yaml
- https://github.com/wikimedia/mediawiki
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/RTTPZ7XMDS66I442OLLHXBDNP2LCBJU6
- https://lists.wikimedia.org/pipermail/mediawiki-announce
- https://lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048480.html
- https://lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048488.html
- https://phabricator.wikimedia.org/T115888
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N- Weakness (CWE)
CWE-79- Platform
- Composer
- Package
mediawiki/core- Disclosed
- 24.05.2022
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-h8qx-mj6v-2934 - CC BY 4.0
Vulnerability history: mediawiki/core
All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 28
- First → latest
- 05.2022 10.2023
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 2
- High 6
- Medium 20
Disclosures per year
- 2022: 26
- 2023: 2
- 2024: 0
- 2025: 0
- 2026: 0
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MediaWiki Cross-site Scripting (XSS) vulnerability this entry
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