Vulnerability · Published Apr 7, 2026 · Assigned by wikimedia-foundation

CVE-2026-39936Stored XSS in Score due to usage of non-reserved data attributes

Medium 6.9

In plain English

A medium-severity cross-site scripting in Mediawiki - Score Extension from The Wikimedia Foundation. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 20% of all known vulnerabilities).

Severity (CVSS 4.0)6.9Medium
Exploit odds (30 days)0.3%top 79.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known

Official description

Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in The Wikimedia Foundation Mediawiki - Score Extension allows Cross-Site Scripting (XSS). The issue has been remediated on the `master` branch, and in the release branches for MediaWiki versions 1.43, 1.44, and 1.45.

Affected products (as reported)

VendorProductVersions
The Wikimedia Foundation Mediawiki - Score Extension 0 – before 1.43

Weakness: CWE-79 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L

References