A Reflected Cross-Site Scripting (XSS) vulnerability in GetSimple CMS v3.3.16, in the admin/index.php login portal webpage, allows remote attackers to execute JavaScript code in the client's browser and harvest login credentials after a client clicks a link, enters credentials, and submits the login form.

Multiple cross-site scripting (XSS) vulnerabilities in GetSimple CMS before 3.2.1 allow remote attackers to inject arbitrary web script or HTML via the (1) id parameter to backup-edit.php; (2) title or (3) menu parameter to edit.php; or (4) path or (5) returnid parameter to filebrowser.php in admin/. NOTE: the path parameter in admin/upload.php vector is already covered by CVE-2012-6621.

GetSimple CMS v3.3.15 has Persistent Cross-Site Scripting (XSS) in admin/theme-edit.php.

An issue was discovered in GetSimple CMS through 3.3.15. insufficient input sanitation in the theme-edit.php file allows upload of files with arbitrary content (PHP code, for example). This vulnerability is triggered by an authenticated user; however, authentication can be bypassed. According to the official documentation for installation step 10, an admin is required to upload all the files, including the .htaccess files, and run a health check. However, what is overlooked is that the Apache HTTP Server by default no longer enables the AllowOverride directive, leading to data/users/admin.xml password exposure. The passwords are hashed but this can be bypassed by starting with the data/other/authorization.xml API key. This allows one to target the session state, since they decided to roll their own implementation. The cookie_name is crafted information that can be leaked from the frontend (site name and version). If a someone leaks the API key and the admin username, then they can byp…

GetSimpleCMS 3.3.13 has an Open Redirect via the admin/index.php redirect parameter.

There is Stored XSS in GetSimple CMS 3.3.12 via the admin/edit.php "post-menu" parameter, a related issue to CVE-2018-16325.

In GetSimpleCMS 3.3.15, admin/upload.php blocks .html uploads but there are several alternative cases in which HTML can be executed, such as a file with no extension or an unrecognized extension (e.g., the test or test.asdf filename), because of admin/upload-uploadify.php, and validate_safe_file in admin/inc/security_functions.php.

In GetSimpleCMS 3.3.15, admin/upload.php blocks .html uploads but Internet Explorer render HTML elements in a .eml file, because of admin/upload-uploadify.php, and validate_safe_file in admin/inc/security_functions.php.

An issue was discovered in GetSimple CMS 3.3.15. An administrator can insert stored XSS via the admin/settings.php Custom Permalink Structure parameter, which injects the XSS payload into any page created at the admin/pages.php URI.

An issue was discovered in GetSimple CMS v3.3.13. There is a CSRF vulnerability that can change the administrator's password via admin/settings.php. NOTE: The vendor reported that the PoC was sending a value for the nonce parameter