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.

A command injection remote code execution vulnerability was discovered on Western Digital My Cloud Devices that could allow an attacker to execute arbitrary system commands on the device. The vulnerability was addressed by escaping individual arguments to shell functions coming from user input.

An issue was discovered on Western Digital My Cloud NAS devices before 5.04.114. They allow remote code execution with resultant escalation of privileges.

It was discovered that the Western Digital My Cloud device before 2.30.196 is affected by an authentication bypass vulnerability. An unauthenticated attacker can exploit this vulnerability to authenticate as an admin user without needing to provide a password, thereby gaining full control of the device. (Whenever an admin logs into My Cloud, a server-side session is created that is bound to the user's IP address. After the session is created, it is possible to call authenticated CGI modules by sending the cookie username=admin in the HTTP request. The invoked CGI will check if a valid session is present and bound to the user's IP address.) It was found that it is possible for an unauthenticated attacker to create a valid session without a login. The networkmgr.cgi CGI module contains a command called "cgigetipv6" that starts an admin session -- tied to the IP address of the user making the request -- if the additional parameter "flag" with the value "1" is provided. Subsequent invocation of commands that would normally require admin privileges now succeed if an attacker sets the username=admin cookie.

Western Digital My Cloud, My Cloud Home, My Cloud Home Duo, and SanDisk ibi devices were vulnerable to an impersonation attack that could allow an unauthenticated attacker to gain access to user data. This issue affects My Cloud OS 5 devices: before 5.25.132; My Cloud Home and My Cloud Home Duo: before 8.13.1-102; SanDisk ibi: before 8.13.1-102.

An authentication bypass issue via spoofing was discovered in the token-based authentication mechanism that could allow an attacker to carry out an impersonation attack.

This issue affects My Cloud OS 5 devices: before 5.26.202.

On Western Digital My Cloud OS 5 devices before 5.06.115, the NAS Admin dashboard has an authentication bypass vulnerability that could allow an unauthenticated user to execute privileged commands on the device.

An issue was discovered on Western Digital My Cloud OS 5 devices before 5.06.115. A NAS Admin authentication bypass vulnerability could allow an unauthenticated user to execute privileged commands on the device via a cookie, because of insufficient validation of URI paths.

An issue was discovered on Western Digital My Cloud OS 5 devices before 5.06.115. A NAS Admin authentication bypass vulnerability could allow an unauthenticated user to execute privileged commands on the device via a cookie. (In addition, an upload endpoint could then be used by an authenticated administrator to upload executable PHP scripts.)

An issue was discovered on Western Digital My Cloud OS 5 devices before 5.07.118. A NAS Admin authentication bypass vulnerability could allow an unauthenticated user to gain access to the device.

A remote code execution vulnerability was discovered on Western Digital My Cloud devices where an attacker could trick a NAS device into loading through an unsecured HTTP call. This was a result insufficient verification of calls to the device. The vulnerability was addressed by disabling checks for internet connectivity using HTTP.

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 loginmgr.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.

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 unauthenticated file upload vulnerability. The page web/jquery/uploader/uploadify.php can be accessed without any credentials, and allows uploading arbitrary files to any location on the attached storage.

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.

Improper Neutralization of Special Elements used in a Command ('Command Injection') vulnerability that could allow an attacker to execute code in the context of the root user on a vulnerable CGI file was discovered in Western Digital My Cloud OS 5 devicesThis issue affects My Cloud OS 5: before 5.26.119.

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') vulnerability that was caused by a command that read files from a privileged location and created a system command without sanitizing the read data. This command could be triggered by an attacker remotely to cause code execution and gain a reverse shell in Western Digital My Cloud OS 5 devices.This issue affects My Cloud OS 5: before 5.26.119.

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability that could allow an attacker to write files to locations with certain critical filesystem types leading to remote code execution was discovered in Western Digital My Cloud Home, My Cloud Home Duo, SanDisk ibi and Western Digital My Cloud OS 5 devices. This issue requires an authentication bypass issue to be triggered before this can be exploited.  This issue affects My Cloud Home and My Cloud Home Duo: before 9.4.0-191; ibi: before 9.4.0-191; My Cloud OS 5: before 5.26.202.

Western Digital My Cloud EX2 Ultra firmware 2.31.195 allows a Buffer Overflow with Extended Instruction Pointer (EIP) control via crafted GET/POST parameters.

Western Digital My Cloud EX2 Ultra firmware 2.31.183 allows web users (including guest accounts) to remotely execute arbitrary code via a downloadmgr.cgi stack-based buffer overflow.

Western Digital My Cloud EX2 Ultra firmware 2.31.183 allows web users (including guest account) to remotely execute arbitrary code via a stack-based buffer overflow. There is no size verification logic in one of functions in libscheddl.so, and downloadmgr.cgi makes it possible to enter large-sized fidx inputs.

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/webfilemgr.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 "cgiuntar" command. Other commands might also be susceptible. Code can be executed because the "name" parameter passed to the cgiunzip command is not sanitized.

A limited authentication bypass vulnerability was discovered that could allow an attacker to achieve remote code execution and escalate privileges on the My Cloud devices. Addressed this vulnerability by changing access token validation logic and rewriting rule logic on PHP scripts.

A limited SSRF vulnerability was discovered on Western Digital My Cloud devices that could allow an attacker to impersonate a server and reach any page on the server by bypassing access controls. The vulnerability was addressed by creating a whitelist for valid parameters.

A malicious user on the same LAN could use DNS spoofing followed by a command injection attack to trick a NAS device into loading through an unsecured HTTP call. Addressed this vulnerability by disabling checks for internet connectivity using HTTP.

A post-authentication remote command injection vulnerability in a CGI file in Western Digital My Cloud OS 5 devices that could allow an attacker to build files with redirects and execute larger payloads. This issue affects My Cloud OS 5 devices: before 5.26.300.

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.

The Western Digital My Cloud Web App [https://os5.mycloud.com/] uses a weak SSLContext when attempting to configure port forwarding rules. This was enabled to maintain compatibility with old or outdated home routers. By using an "SSL" context instead of "TLS" or specifying stronger validation, deprecated or insecure protocols are permitted. As a result, a local user with no privileges can exploit this vulnerability and jeopardize the integrity, confidentiality and authenticity of information transmitted. The scope of impact cannot extend to other components and no user input is required to exploit this vulnerability.

Post-authentication remote command injection vulnerability in Western Digital My Cloud OS 5 devices that could allow an attacker to execute code in the context of the root user on vulnerable CGI files. This vulnerability can only be exploited over the network and the attacker must already have admin/root privileges to carry out the exploit. An authentication bypass is required for this exploit, thereby making it more complex. The attack may not require user interaction. Since an attacker must already be authenticated, the confidentiality impact is low while the integrity and availability impact is high.

This issue affects My Cloud OS 5 devices: before 5.26.300.

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability that could allow an attacker to create arbitrary shares on arbitrary directories and exfiltrate sensitive files, passwords, users and device configurations was discovered in Western Digital My Cloud Home, My Cloud Home Duo, SanDisk ibi and Western Digital My Cloud OS 5 devices. This can only be exploited once an attacker gains root privileges on the devices using an authentication bypass issue or another vulnerability.This issue affects My Cloud Home and My Cloud Home Duo: before 9.4.0-191; ibi: before 9.4.0-191; My Cloud OS 5: before 5.26.202.