Vulnerability · Published Jul 1, 2026 · Assigned by wikimedia-foundation

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

Medium 5.3

In plain English

A medium-severity cross-site scripting in MediaWiki from Wikimedia Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 23% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)5.3Medium

Exploit odds (30 days)0.3%top 77.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	mediawiki	no fix listed	DEBIAN-CVE-2026-58032
Debian:13	mediawiki	1:1.43.9+dfsg-1~deb13u1	DEBIAN-CVE-2026-58032
Debian:14	mediawiki	1:1.43.9+dfsg-1	DEBIAN-CVE-2026-58032
Ubuntu:25.10	mediawiki	no fix listed	UBUNTU-CVE-2026-58032
Ubuntu:26.04:LTS	mediawiki	no fix listed	UBUNTU-CVE-2026-58032
Ubuntu:26.10	mediawiki	no fix listed	UBUNTU-CVE-2026-58032

Affected products (as reported)

Vendor	Product	Versions
Wikimedia Foundation	MediaWiki	* – before 1.46.0, 1.45.4, 1.44.6, 1.43.9

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

References

https://phabricator.wikimedia.org/T426867