XSS in Anssilaitila Contact List – Online Staff Directory & Address Book
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.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.003 (19.4th 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
Weakness classification (CWE)
Public proof-of-concept exploits
References
Frequently asked questions
- What is CVE-2026-3516?
- CVE-2026-3516 is a medium-severity vulnerability in Anssilaitila Contact List – Online Staff Directory & Address Book, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-03-21.
- How severe is CVE-2026-3516?
- Medium severity. CVSS v3 base score is 6.4 out of 10.
- Is CVE-2026-3516 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.