CVE-2020-18657: Get-Simple Getsimplecms

Medium severity, CVSS 6.1. EPSS: 1.4% chance of exploitation in the next 30 days.

Cross Site Scripting (XSS) vulnerability in GetSimpleCMS <= 3.3.15 in admin/changedata.php via the redirect_url parameter and the headers_sent function.

Affected products

• Get-Simple Getsimplecms: up to and including 3.3.15

Published 2021-06-23. Last modified 2026-06-17.