SB2018010805 - Backdoor in D-Link DNS-320L/LW ShareCenter



SB2018010805 - Backdoor in D-Link DNS-320L/LW ShareCenter

Published: January 8, 2018

Security Bulletin ID SB2018010805
Severity
High
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

Critical 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 security vulnerability.


1) Hidden functionality (backdoor) (CVE-ID: N/A)

The vulnerability allows a remote attacker to gain unauthorized access to vulnerable device.

The vulnerability exists due to presence of a backdoor code (hard-coded account credentials) in firmware shared by WD My Cloud and D-LINK DNS-320L ShareCenter software. A remote attacker can send a specially crafted HTTP GET request to the affected device and gain unauthorized access to it.

Exploitation example:
 GET /cgi-bin/nas_sharing.cgi?dbg=1&cmd=51&user=mydlinkBRionyg&passwd=YWJjMTIzNDVjYmE&start=1&count=1;touch+/tmp/gulftech; HTTP/1.1

where login is "mydlinkBRionyg" and password is "abc12345cba".

List of affected Western Digital devices:

               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
               My Cloud DL4100
               My Cloud DL4100

Note: this vulnerability was updated according to GulfTech advisory. Vulnerability severity is raised to critical and this vulnerability is being treated as a zero-day.


Remediation

Install update from vendor's website.