What the vulnerability does
01Description
The CM E-Mail Blacklist – Simple email filtering for safer registration plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'black_email' parameter in all versions up to, and including, 1.6.2. This is due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with administrator-level access and above, 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.
Explanation of Vulnerability in Simple Terms
02Summary
CM E-Mail Blacklist versions 1.6.2 and earlier contain a cross-site scripting (XSS) vulnerability in the admin interface. An authenticated administrator with high privileges can inject malicious scripts that execute in the browser of other users viewing the plugin's pages. The vulnerability requires high attack complexity and does not require user interaction from the victim.
What an attacker can do
03Attacker Capabilities
Inject malicious scripts that run in other users' browsers when they view the plugin's admin pages.
Potential impact on your site
04Site Impact
A malicious admin could steal session tokens or perform actions on behalf of other administrators viewing the plugin.
Conditions required to exploit
05Prerequisites
Attacker must be an authenticated administrator with high-level privileges on the site.
Key dates
06Disclosure timeline
January 17, 2026
CVE published
April 8, 2026
Record updated
