What is CVE-2024-34500?

CVE-2024-34500 is a medium-severity vulnerability in MediaWiki, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2024-05-05.

How severe is CVE-2024-34500?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in MediaWiki

CVE-2024-34500

An issue was discovered in the UnlinkedWikibase extension in MediaWiki before 1.39.6, 1.40.x before 1.40.2, and 1.41.x before 1.41.1. XSS can occur through an interface message. Error messages (in the $err var) are not escaped before being passed to Html::rawElement() in the getError() function in the Hooks class.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2024-05-05 · last modified 2026-06-17.

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: 0.005 (38.5th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 38.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

MediaWiki
Fedoraproject Fedora — versions 40

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

phabricator.wikimedia.org/T357203 (Issue Tracking, Vendor Advisory)
gerrit.wikimedia.org/r/c/mediawiki/extensions/UnlinkedWikibase/+/1002175 (Patch, Vendor Advisory)
lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory, Third Party Advisory)
af854a3a-2127-422b-91ae-364da2661108

Frequently asked questions

What is CVE-2024-34500?: CVE-2024-34500 is a medium-severity vulnerability in MediaWiki, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2024-05-05.
How severe is CVE-2024-34500?: Medium severity. CVSS v3 base score is 6.1 out of 10.