CVE-2026-3516: The Contact List plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the '_cl_map_iframe' parameter in all versions up to, and inclu...

Description

The Contact List plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the '_cl_map_iframe' parameter in all versions up to, and including, 3.0.18. This is due to insufficient input sanitization and output escaping when handling the Google Maps iframe custom field. The saveCustomFields() function in class-contact-list-custom-fields.php uses a regex to extract <iframe> tags from user input but does not validate or sanitize the iframe's attributes, allowing event handlers like 'onload' to be included. The extracted iframe HTML is stored via update_post_meta() and later rendered on the front-end in class-cl-public-card.php without any escaping or wp_kses filtering. 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.

Metrics

CVSS 3.1

6.4/10

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

EPSS Probability

0.27%

18.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

References

Timeline

Published: Mar 21, 2026
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-3516?

The Contact List plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the '_cl_map_iframe' parameter in all versions up to, and including, 3.0.18. This is due to insufficient input sanitization and output escaping when handling the Google Maps iframe custom field. The saveCustomFields() function in class-contact-list-custom-fields.php uses a regex to extract <iframe> tags from user input but does not validate or sanitize the iframe's attributes, allowing event handlers like 'onload' to be included. The extracted iframe HTML is stored via update_post_meta() and later rendered on the front-end in class-cl-public-card.php without any escaping or wp_kses filtering. 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.

How severe is CVE-2026-3516?

CVE-2026-3516 has a CVSS score of 6.4/10 (MEDIUM severity). The EPSS model estimates a 0.27% probability of exploitation in the next 30 days.

How do I fix CVE-2026-3516?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.