Cross-site scripting in File Manager - CVE-2018-16363

Detailed vulnerability description

The vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data when processing the lang parameter in a wp-admin/admin.php?page=wp_file_manager request because set_transient is used in file_folder_manager.php and there is an echo of lang in libwpfilemanager.php. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

How to mitigate CVE-2018-16363

Sources

• https://wordpress.org/support/topic/security-concern-6/#post-10655739
• https://plugins.trac.wordpress.org/changeset/1936043
• http://blog.51cto.com/010bjsoft/2171087