Medium severity · published Apr 7, 2026
CVE-2026-39935
XSS-via-i18n in localised wiki names
6.9
CVSS
0.3%
EPSS
No
On KEV
Description
Improper neutralization of input during web page generation ('cross-site scripting') vulnerability in The Wikimedia Foundation Mediawiki - CampaignEvents Extension allows Cross-Site Scripting (XSS). This issue was remediated only on the `master` branch.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 22% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MC
Mediawiki - CampaignEvents Extension · The Wikimedia Foundation
1.43; 1.44; 1.45; before 1.43 · source: vendor
Affected product
MC
Mediawiki - CampaignEvents Extension
The Wikimedia Foundation