CVE-2026-103584 attacker-controlled javascript license URL via XSS
An attacker can inject malicious JavaScript via a license URL in the MediaWiki CommonsMetadata extension, potentially executing code or hijacking user sessions.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-103584?
CVE-2026-103584 is a low-severity cross-site scripting vulnerability in The Wikimedia Foundation MediaWiki CommonsMetadata extension, published on 30 Sep 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Official description
Improper neutralization of Script-Related HTML tags in a web page (basic XSS) vulnerability in The Wikimedia Foundation MediaWiki CommonsMetadata extension allows Cross-Site Scripting (XSS).
This issue affects MediaWiki CommonsMetadata extension: 1.46, 1.45, and 1.43.
Weakness: CWE-80
Which versions are affected by CVE-2026-103584?
How do I fix CVE-2026-103584?
No fix has been published for CVE-2026-103584 yet. Limit exposure of the affected software until one is available.
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-2026-103584 being exploited?
There is no known exploitation of CVE-2026-103584 in the wild and no public exploit code.
Public exploit code: 1 proofs of concept on GitHub.
Sources
Also known as GHSA-v276-8895-8m7m.