my_cloud_pr4100_firmware

Western Digital My Cloud Cloud, Mirror Gen2, EX2 Ultra, EX2100, EX4100, DL2100, DL4100, PR2100 and PR4100 before firmware 2.31.183 are affected by a code execution (as root, starting from a low-privilege user session) vulnerability. The cgi-bin/webfile_mgr.cgi file allows arbitrary file write by abusing symlinks. Specifically, this occurs by uploading a tar archive that contains a symbolic link, then uploading another archive that writes a file to the link using the “cgi_untar” command. Other commands might also be susceptible. Code can be executed because the “name” parameter passed to the cgi_unzip command is not sanitized.

Western Digital My Cloud, My Cloud Mirror Gen2, My Cloud EX2 Ultra, My Cloud EX2100, My Cloud EX4100, My Cloud DL2100, My Cloud DL4100, My Cloud PR2100 and My Cloud PR4100 firmware before 2.31.174 is affected by an authentication bypass vulnerability. The login_mgr.cgi file checks credentials against /etc/shadow. However, the “nobody” account (which can be used to access the control panel API as a low-privilege logged-in user) has a default empty password, allowing an attacker to modify the My Cloud EX2 Ultra web page source code and obtain access to the My Cloud as a non-Admin My Cloud device user.

A command injection vulnerability in the DDNS service configuration of Western Digital My Cloud OS 5 devices running firmware versions prior to 5.26.119 allows an attacker to execute code in the context of the root user.

A vulnerability in the FTP service of Western Digital My Cloud OS 5 devices running firmware versions prior to 5.26.119 allows an attacker to read and write arbitrary files. This could lead to a full NAS compromise and would give remote execution capabilities to the attacker.

The combination of primitives offered by SMB and AFP in their default configuration allows the arbitrary writing of files. By exploiting these combination of primitives, an attacker can execute arbitrary code.

Western Digital My Cloud devices are vulnerable to a cross side scripting vulnerability that can allow a malicious user with elevated privileges access to drives being backed up to construct and inject JavaScript payloads into an authenticated user’s browser. As a result, it may be possible to gain control over the authenticated session, steal data, modify settings, or redirect the user to malicious websites. The scope of impact can extend to other components.