PT-2026-30991 · Wikimedia Foundation · Mediawiki+1

Somerandomdeveloper · Published 2026-04-07 · Updated 2026-04-07 · CVE-2026-39838

Positive Technologies (AI Summary)

CVSS v4.0

6.9

Medium

Base vector

AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Name of the Vulnerable Software and Affected Versions Wikimedia Foundation MediaWiki - ProofreadPage Extension (affected versions not specified)

Description A cross-site scripting issue exists in the ProofreadPage Extension. The issue is due to improper neutralization of input during web page generation, allowing for potential cross-site scripting attacks targeting non-script elements.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

XSS

Weakness Enumeration

CWE-79

Related Identifiers

CVE-2026-39838

Affected Products

Mediawiki

Proofreadpage Extension

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-39838 · Security Note
• https://twitter.com/CVEnew/status/2041603142437961865 · Twitter Post
• https://gerrit.wikimedia.org/r/q/Idd51e18479b32b7176b43ff74ca1c49d6bdd0628 · Note
• https://phabricator.wikimedia.org/T406088 · Note