#VU9872 Unrestricted file upload in WD My Cloud

Vulnerability identifier: #VU9872

Vulnerability risk: High

CVSSv4.0: 8.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Amber]

CVE-ID: N/A

CWE-ID: CWE-434

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
WD My Cloud
Hardware solutions / Office equipment, IP-phones, print servers

Vendor: Western Digital

Description
The vulnerability allows a remote attacker to compromise vulnerable device.

The vulnerability exists due to improper validation of file extension in "/usr/local/modules/web/pages/jquery/uploader/multi_uploadify.php" scrpit before uploading files via the "/mydlink/mydlink.cgi" URI. A remote unauthenticated attacker can send a specially crafted HTTP POST request to vulnerable device and upload arbitrary file on the system.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable device.

Note: description of this vulnerability was updated according to GulfTech advisory.

Mitigation
Update to version 2.30.172.

Vulnerable software versions

WD My Cloud: 2.10.302 - 2.30.165

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External links
https://support.wdc.com/download/notes/WD_My_Cloud_Firmware_Release_Notes_2.30.172.pdf?v=987
https://gulftech.org/advisories/WDMyCloud%20Multiple%20Vulnerabilities/125

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.