WordPress Continually Plugin Stored Cross-Site Scripting Vulnerability

A stored cross-site scripting vulnerability has been identified in the Continually plugin for WordPress, affecting all versions up to and including 4.3.1. The issue arises from inadequate input sanitization and output escaping, allowing authenticated attackers with administrator-level permissions to inject arbitrary web scripts. These scripts are executed when a user accesses the affected page. This vulnerability is present in multi-site installations where unfiltered_html has been disabled.

Impact

Exploitation of this vulnerability allows for stored cross-site scripting, where injected scripts are executed in the context of the user viewing the page.

Reproduction

To reproduce this vulnerability, an authenticated user with administrator-level permissions must inject a script into the 'continually_embed_code' parameter via the admin settings. Once injected, the script will execute when the page is accessed by any user.

Remediation

No known patch is available. It is recommended to uninstall the affected plugin and find a replacement.