XSS in Star-Citizen Embedvideo

CVE-2025-59839

The EmbedVideo Extension is a MediaWiki extension which adds a parser function called #ev and various parser tags for embedding video clips from various video sharing services. In versions 4.0.0 and prior, the EmbedVideo extension allows adding arbitrary attributes to an HTML element, allowing for stored XSS through wikitext. This issue has been patched via commit 4e075d3.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.003 (20.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-59839?
CVE-2025-59839 is a high-severity vulnerability in Star-Citizen Embedvideo, classified under Cross-site Scripting. CVSS score: 8.6/10. Published 2025-09-25.
How severe is CVE-2025-59839?
High severity. CVSS v3 base score is 8.6 out of 10.
Is CVE-2025-59839 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.