XSS in MediaWiki
CVE-2020-25828
An issue was discovered in MediaWiki before 1.31.10 and 1.32.x through 1.34.x before 1.34.4. 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.)
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.011 (64.1th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 64.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000
Affected products
- MediaWiki — versions 1.31.10
- Fedoraproject Fedora — versions 33
Weakness classification (CWE)
References
- lists.wikimedia.org/pipermail/mediawiki-announce (Vendor Advisory)
- lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048480.html (Mailing List, Vendor Advisory)
- lists.wikimedia.org/pipermail/mediawiki-l/2020-September/048488.html (Mailing List, Vendor Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
Frequently asked questions
- What is CVE-2020-25828?
- CVE-2020-25828 is a medium-severity vulnerability in MediaWiki, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2020-09-27.
- How severe is CVE-2020-25828?
- Medium severity. CVSS v3 base score is 6.1 out of 10.