CVE-2026-3090
CWE-79Published: March 18, 2026· Updated: Mar 19, 2026
Official 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.
Technical Analysis
CVE-2026-3090 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.
From a weakness classification perspective (CWE-79): Cross-site scripting (XSS) vulnerabilities allow attackers to inject malicious scripts into web pages viewed by other users.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (3)
Quick Facts
Related CVEs (CWE-79)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-3090 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts