XSS in Demonisblack Scoreboard For Html5 Games Lite
CVE-2026-4083
The Scoreboard for HTML5 Games Lite plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'scoreboard' shortcode in all versions up to, and including, 1.2. The shortcode function sfhg_shortcode() allows arbitrary HTML attributes to be added to the rendered <iframe> element, with only a small blacklist of four attribute names (same_height_as, onload, onpageshow, onclick) being blocked. While the attribute names are passed through esc_html() and values through esc_attr(), this does not prevent injection of JavaScript event handler attributes like onfocus, onmouseover, onmouseenter, etc., because these attribute names and simple JavaScript payloads contain no characters that would be modified by these escaping functions. The shortcode text is stored in post_content and is only expanded to HTML at render time, after WordPress's kses filtering has already been applied to the raw post content. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.002 (10.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.
Affected products
- Demonisblack Scoreboard For Html5 Games Lite — versions 0
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-4083?
- CVE-2026-4083 is a medium-severity vulnerability in Demonisblack Scoreboard For Html5 Games Lite, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-03-21.
- How severe is CVE-2026-4083?
- Medium severity. CVSS v3 base score is 6.4 out of 10.