Western Digital has recently addressed a critical security vulnerability affecting multiple models of its My Cloud network-attached storage (NAS) devices. This flaw, identified as CVE-2025-30247, enables remote attackers to execute arbitrary code on vulnerable systems, potentially leading to full device compromise.
Understanding the Vulnerability
The vulnerability resides in the firmware of various My Cloud devices. If exploited, an unauthenticated attacker could gain control over the NAS device, leading to severe consequences such as data theft, deployment of malware or ransomware, or integration of the device into a botnet for further malicious activities. Given that NAS devices often store sensitive personal and business data, the impact of such a compromise could be significant.
Affected Devices
The following My Cloud models are confirmed to be affected by this vulnerability:
– My Cloud PR2100
– My Cloud PR4100
– My Cloud EX4100
– My Cloud EX2 Ultra
– My Cloud Mirror Gen 2
– My Cloud DL2100
– My Cloud EX2100
– My Cloud DL4100
– My Cloud WDBCTLxxxxxx-10
– My Cloud
Mitigation Measures
To address this critical issue, Western Digital has released firmware version 5.31.108 on September 24, 2025. Users are strongly urged to update their devices to this latest firmware version to mitigate the risk associated with CVE-2025-30247. The update can be applied directly through the firmware update notification within the device’s administrative interface.
Steps to Update Firmware
1. Log in to the My Cloud device’s web interface.
2. Navigate to the Settings section.
3. Click on Firmware Update.
4. If an update is available, follow the on-screen instructions to download and install the latest firmware.
Acknowledgment
Western Digital has credited security researcher w1th0ut for discovering and responsibly reporting the vulnerability, allowing the company to develop and issue a timely patch.
Importance of Timely Updates
This incident underscores the ongoing security risks associated with internet-connected storage devices. Threat actors frequently scan for and target unpatched NAS systems due to the valuable data they contain. Applying security patches as soon as they become available is one of the most effective measures users can take to protect their data from unauthorized access and cyberattacks.
Additional Security Recommendations
– Enable Automatic Updates: Where possible, configure your device to automatically install firmware updates to ensure timely protection against vulnerabilities.
– Regularly Monitor Device Logs: Keep an eye on system logs for any unusual activity that might indicate a security breach.
– Implement Network Segmentation: Isolate NAS devices from the public internet and place them behind a firewall to reduce exposure to potential attacks.
– Use Strong, Unique Passwords: Ensure that all user accounts on the NAS device have strong, unique passwords to prevent unauthorized access.
Conclusion
The discovery and patching of CVE-2025-30247 highlight the critical importance of maintaining up-to-date firmware on all network-connected devices. Users of Western Digital My Cloud NAS devices should take immediate action to update their firmware to version 5.31.108 or later to safeguard their data and maintain the integrity of their storage systems.
