CVE-2026-3090

High

Description

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.

SeverityHigh
CVSS7.2
Exploit probability—
ProductPost SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App
PublishedMar 18, 2026
First seenMar 18, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
saadiqbal Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile Appv ≤ 3.8.0—

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CVE-2026-3090 · Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App · Dark Radar