Vulnerability Description
The WPMK Block plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'class' shortcode attribute in all versions up to and including 1.0.1. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes. Specifically, in the wpmk_block_shortcode() function, the 'class' attribute is extracted from user-controllable shortcode attributes and directly concatenated into an HTML div element's class attribute without any escaping (e.g., esc_attr()). 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.
CVSS Score
MEDIUM
Related Weaknesses (CWE)
References
- https://plugins.trac.wordpress.org/browser/wpmk-block/tags/1.0.1/classes/wpmk-bl
- https://plugins.trac.wordpress.org/browser/wpmk-block/tags/1.0.1/classes/wpmk-bl
- https://plugins.trac.wordpress.org/browser/wpmk-block/trunk/classes/wpmk-block-c
- https://plugins.trac.wordpress.org/browser/wpmk-block/trunk/classes/wpmk-block-c
- https://www.wordfence.com/threat-intel/vulnerabilities/id/5e397c7a-2aef-4c23-a22
FAQ
What is CVE-2026-4125?
CVE-2026-4125 is a vulnerability with a CVSS score of 6.4 (MEDIUM). The WPMK Block plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'class' shortcode attribute in all versions up to and including 1.0.1. This is due to insufficient input saniti...
How severe is CVE-2026-4125?
CVE-2026-4125 has been rated MEDIUM with a CVSS base score of 6.4/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-4125?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.