What is CVE-2026-39837?

CVE-2026-39837 is a medium-severity vulnerability in Mediawiki Cargo, classified under Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS). CVSS score: 5.4/10. Published 2026-04-07.

How severe is CVE-2026-39837?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Mediawiki Cargo

CVE-2026-39837

Improper neutralization of Script-Related HTML tags in a web page (basic XSS) vulnerability in WikiWorks Mediawiki - Cargo Extension allows Stored XSS.This issue affects Mediawiki - Cargo Extension: before 3.8.7.

EPSS: 0.002 (8.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Affected products

Mediawiki Cargo
Wikimedia Foundation Mediawiki - Cargo Extension — versions 0

Weakness classification (CWE)

CWE-80 — Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

References

c4f26cc8-17ff-4c99-b5e2-38fc1793eacc (Exploit, Issue Tracking, Vendor Advisory)
c4f26cc8-17ff-4c99-b5e2-38fc1793eacc (Patch)

Frequently asked questions

What is CVE-2026-39837?: CVE-2026-39837 is a medium-severity vulnerability in Mediawiki Cargo, classified under Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS). CVSS score: 5.4/10. Published 2026-04-07.
How severe is CVE-2026-39837?: Medium severity. CVSS v3 base score is 5.4 out of 10.