CVE-2025-4611: Slim SEO <= 4.5.3 - Authenticated (Contributor+) Stored Cross-Site Scripting via slim_seo_breadcrumbs Shortcode
Description
The Slim SEO – Fast & Automated WordPress SEO Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's slim_seo_breadcrumbs shortcode in all versions up to, and including, 4.5.3 due to insufficient input sanitization and output escaping on user supplied attributes. 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.
Classification
CVE ID: CVE-2025-4611
CVSS Base Severity: MEDIUM
CVSS Base Score: 6.4
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Problem Types
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')Affected Products
Vendor: rilwis
Product: Slim SEO – Fast & Automated WordPress SEO Plugin
Exploit Prediction Scoring System (EPSS)
EPSS Score: 0.04% (probability of being exploited)
EPSS Percentile: 11.7% (scored less or equal to compared to others)
EPSS Date: 2025-06-06 (when was this score calculated)
References
https://nvd.nist.gov/vuln/detail/CVE-2025-4611https://www.wordfence.com/threat-intel/vulnerabilities/id/6318a1cf-716f-450c-a1c2-497de8095daa?source=cve
https://wordpress.org/plugins/slim-seo/#developers
https://plugins.trac.wordpress.org/browser/slim-seo/tags/4.5.3/src/Breadcrumbs.php#L37
https://plugins.trac.wordpress.org/browser/slim-seo/tags/4.5.3/src/Breadcrumbs.php#L85
https://plugins.trac.wordpress.org/browser/slim-seo/tags/4.5.3/src/Breadcrumbs.php#L109
https://github.com/elightup/slim-seo/commit/b475dceff3a6bd94335d5a79eb12cdd92e2c8350
https://plugins.trac.wordpress.org/changeset/3296099/