CVE-2026-4125

medium

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.

References

https://www.wordfence.com/threat-intel/vulnerabilities/id/5e397c7a-2aef-4c23-a224-e324ea4bb4b1?source=cve

https://plugins.trac.wordpress.org/browser/wpmk-block/trunk/classes/wpmk-block-class.php#L97

https://plugins.trac.wordpress.org/browser/wpmk-block/trunk/classes/wpmk-block-class.php#L82

https://plugins.trac.wordpress.org/browser/wpmk-block/tags/1.0.1/classes/wpmk-block-class.php#L97

https://plugins.trac.wordpress.org/browser/wpmk-block/tags/1.0.1/classes/wpmk-block-class.php#L82

Details

Source: Mitre, NVD

Published: 2026-04-22

Updated: 2026-04-22

Risk Information

CVSS v2

Base Score: 5.5

Vector: CVSS2#AV:N/AC:L/Au:S/C:P/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 6.4

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Severity: Medium

EPSS

EPSS: 0.00011