What the vulnerability does
01Description
The Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the ‘event_type’ parameter in all versions up to, and including, 3.8.0 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. The vulnerability is only exploitable when the Post SMTP Pro plugin is also installed and its Reporting and Tracking extension is enabled.
Explanation of Vulnerability in Simple Terms
02Summary
Post SMTP versions up to 3.8.0 contain a cross-site scripting (XSS) vulnerability that allows unauthenticated attackers to inject malicious scripts into the site. The vulnerability affects the plugin's scope across the application, potentially impacting multiple users and components. An attacker can read or modify page content and user data without needing authentication or user interaction.
What an attacker can do
03Attacker Capabilities
Inject malicious JavaScript that runs in users' browsers and steals data or modifies site content.
Potential impact on your site
04Site Impact
Attackers can deface your site, steal admin session tokens, or redirect users to malicious sites without your knowledge.
Conditions required to exploit
05Prerequisites
Network access only; no authentication or user interaction required.
Key dates
06Disclosure timeline
March 18, 2026
CVE published
April 8, 2026
Record updated
