CVE-2026-58032 mw.Api.getErrorMessage() may return injected HTML if used without errorformat=html

Medium 5.3 Published 1 Jul 2026 Updated 1 Jul 2026

An attacker can inject HTML into error messages via the API, potentially leading to cross-site scripting attacks in MediaWiki installations.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: A user has to click or open something
Fix: Available

What is CVE-2026-58032?

CVE-2026-58032 is a medium-severity cross-site scripting vulnerability in Mediawiki Mediawiki, published on 1 Jul 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation MediaWiki.

This vulnerability is associated with program files resources/src/mediawiki.Api/index.Js.

This issue affects MediaWiki: from * before 1.46.0, 1.45.4, 1.44.6, 1.43.9.

Weakness: CWE-79

Which versions are affected by CVE-2026-58032?

It affects 1 product.

Products include Mediawiki Mediawiki.

How do I fix CVE-2026-58032?

Upgrade to a fixed version.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2026-58032 being exploited?

There is no known exploitation of CVE-2026-58032 in the wild and no public exploit code.

All Mediawiki Mediawiki vulnerabilities

Sources

Also known as DEBIAN-CVE-2026-58032, GHSA-2pj3-wqpx-g8cm, MINI-3x24-556p-pqmg, MINI-mx92-488m-3jxj, MINI-rhfw-4pjv-h2c4, UBUNTU-CVE-2026-58032.