Western Digital WD My Cloud v04.05.00-320 devices embed the session token (aka PHPSESSID) in filenames, which makes it easier for attackers to bypass authentication by listing a directory. NOTE: this can be exploited in conjunction with CVE-2018-7171 for remote authentication bypass within a product that uses My Cloud.

An issue was discovered on Western Digital MyCloud PR4100 2.30.172 devices. The web administration component, /web/jquery/uploader/multi_uploadify.php, provides multipart upload functionality that is accessible without authentication and can be used to place a file anywhere on the device's file system. This allows an attacker the ability to upload a PHP shell onto the device and obtain arbitrary code execution as root.

The WD My Cloud (aka com.wdc.wd2go) application 4.0.0 for Android does not verify X.509 certificates from SSL servers, which allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate.