What’s Vulnerable › Vulnerabilities

CVE-2025-4611: Slim SEO <= 4.5.3 - Authenticated (Contributor+) Stored Cross-Site Scripting via slim_seo_breadcrumbs Shortcode

• Severity: medium (CVSS 6.4 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-05-21 · updated 2026-06-17
• Weakness: CWE-79

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.

Affected products

• rilwis Slim SEO – A Fast & Automated SEO Plugin For WordPress: through 4.5.3

References

• https://github.com/elightup/slim-seo/commit/b475dceff3a6bd94335d5a79eb12cdd92e2c8350
• https://plugins.trac.wordpress.org/browser/slim-seo/tags/4.5.3/src/Breadcrumbs.php#L109
• 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/changeset/3296099/
• https://wordpress.org/plugins/slim-seo/#developers
• https://www.wordfence.com/threat-intel/vulnerabilities/id/6318a1cf-716f-450c-a1c2-497de8095daa?source=cve

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