CVE-2021-28977

Name of the Vulnerable Software and Affected Versions: GetSimpleCMS version 3.3.16

Description: The issue concerns a Cross Site Scripting vulnerability. It can be exploited in the admin/upload.php file by adding comments or jpg and other file header information to the content of xla, pages, and gzip files.

Recommendations: For GetSimpleCMS version 3.3.16, update to a newer version that contains a fix for this issue, as using outdated versions may pose a security risk. As a temporary workaround, consider restricting access to the admin/upload.php file to minimize the risk of exploitation. Avoid using the vulnerable file upload functionality in the admin/upload.php file until the issue is resolved.