XSS in Metabox Meta Box – A Framework For Dynamic Websites

CVE-2026-109216

The Meta Box – A Framework for Dynamic Websites plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'profile_background[<attacker-chosen key>]' parameter in all versions up to, and including, 5.15.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Exploitability depends on a consuming plugin or theme built on Meta Box that exposes the background field to lower-privileged users and renders stored values via the rwmb_the_value()/format_single_value() pattern; the effective minimum privilege is whatever role that consumer permits, demonstrated at Subscriber level.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-109216?
CVE-2026-109216 is a medium-severity vulnerability in Metabox Meta Box – A Framework For Dynamic Websites, classified under Cross-site Scripting. CVSS score: 4.9/10. Published 2026-10-29.
How severe is CVE-2026-109216?
Medium severity. CVSS v3 base score is 4.9 out of 10.