CVE-2025-4369

The Companion Auto Update plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘update_delay_days’ parameter in all versions up to, and including, 3.9.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.
CVE-2025-4369CVSS 5.5Web

CVE-2025-4369

The Companion Auto Update plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘update_delay_days’ parameter in all versions up to, and including, 3.9.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.

CVSS
5.5 MEDIUM
EPSS
15.38%
Known exploited
not in KEV
Product
-

What is known

The Companion Auto Update plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘update_delay_days’ parameter in all versions up to, and including, 3.9.2 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This only affects multi-site installations and installations where unfiltered_html has been disabled.

Sources

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