HTB23141: Multiple cross-site scripting (XSS) vulnerabilities in GetSimple CMS

GetSimple CMS version 3.1.2 suffers from cross-site scripting vulnerabilities, which can be exploited to perform Cross-Site Scripting (XSS) attacks.

Cross-site scripting (XSS) in GetSimple CMS (CVE-2013-1420): the issues exists due to insufficient sanitisation of user-supplied data passed via the "id" HTTP GET parameter to "/admin/backup-edit.php", "path" HTTP GET parameter to "/admin/upload.php", "title" and "menu" HTTP GET parameters to "/admin/edit.php", "path" and "returnid" HTTP GET parameters to "/admin/filebrowser.php" scripts. A remote attacker can trick a logged-in administrator to open a specially crafted link and execute arbitrary HTML and script code in browser in context of the vulnerable website.

GetSimple CMS has XSS filter, however it can be bypassed as demonstrated in PoC examples of High-Tech Bridge advisory HTB23141.