What’s Vulnerable › Vulnerabilities

CVE-2026-9643: WP Meta SEO <= 4.5.18 - Unauthenticated Stored Cross-Site Scripting via REQUEST_URI in 404 Logging

• Severity: high (CVSS 7.2 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-06-24 · updated 2026-06-29
• Weakness: CWE-79

Description

The WP Meta SEO plugin for WordPress is vulnerable to Unauthenticated Stored Cross-Site Scripting via the REQUEST_URI server variable in all versions up to, and including, 4.5.18. When the plugin's `wpmsTemplateRedirect()` hook detects a 404, it concatenates `$_SERVER['HTTP_HOST']` with the raw `$_SERVER['REQUEST_URI']` and inserts that value verbatim into the `wp_wpms_links.link_url` column via `$wpdb->insert()`. This makes it possible for unauthenticated attackers to inject arbitrary web scripts that execute whenever an administrator views the plugin's 404 & Redirects admin page (`/wp-admin/admin.php?page=metaseo_broken_link`).

Affected products

• joomunited WP Meta SEO: through 4.5.18

References

• https://plugins.trac.wordpress.org/browser/wp-meta-seo/tags/4.5.18/inc/class.metaseo-broken-link-table.php#L894
• https://plugins.trac.wordpress.org/browser/wp-meta-seo/tags/4.5.18/wp-meta-seo.php#L1135
• https://plugins.trac.wordpress.org/browser/wp-meta-seo/tags/4.5.18/wp-meta-seo.php#L1171
• https://plugins.trac.wordpress.org/changeset?old_path=/wp-meta-seo/tags/4.5.12&new_path=/wp-meta-seo/tags/4.5.13
• https://ti.wordfence.io/vulnerabilities/ca91e41d-b728-4eb0-86d5-043813d8c2c1
• https://www.wordfence.com/threat-intel/vulnerabilities/id/beceb218-34bf-4571-a07b-939abc7ead8e?source=cve

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