Shocking enough this is already known publicly since March 2017 or even longer including various PoCs
Exploitee.rs » Blog Archive » Hacking the Western Digital MyCloud NAS (Login Bypass)
Western Digital MyCloud - Exploitee.rs
Not talking about all the other currently publicly known and unfixed vulns:
https://community.wd.com/t/security-vulnerability-cve-2016-6255-in-libupnp-allows-file-upload/176448
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