Among the flaws were unrestricted file upload, the ability to gain a remote root shell, a hard-coded backdoor and other miscellaneous vulnerabilities. There was no protection against cross-site request forgeries or command injection, while a denial-of-service attack was also possible.
James Bercegay of GulfTech Research and Development wrote that he had contacted Western Digital on 19 June to inform them of the vulnerabilities, and received confirmation of the receipt of his message three days later.
Thereafter, he said, the vendor had requested the standard 90 days before full disclosure. Bercegay waited until 15 December when he discovered that someone else had posted a detailed account of one of the bugs.
According to Bercegay, the following devices are affected: MyCloud, MyCloudMirror, My Cloud Gen 2, My Cloud PR2100, My Cloud PR4100, My Cloud EX2 Ultra, My Cloud EX2, My Cloud EX4, My Cloud EX2100, My Cloud EX4100, My Cloud DL2100 and My Cloud DL4100.
However, the MyCloud 04.X Series and MyCloud 2.30.174 were not vulnerable.
"WD My Cloud is a personal cloud storage unit to organise your photos and videos. It is currently the best selling NAS (network attached storage) device listed on the amazon.com website, and is used by individuals and businesses alike," he wrote.
"Its purpose is to host your files, and it also has the ability to sync them with various cloud and Web-based services."
Bercegay said he had uploaded Metasploit modules for the flaws outlined and these could be found online.
iTWire has contacted Western Digital for comment.