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DSR Family Products :: DSR-250 :: Rev. Ax :: F/W v3.17 & Older :: Unauthenticated & Authenticated Command Injection Vulnerabilities

Overview

On August 11, 2020, a 3rd party security researcher submitted a report accusing the DSR-250 Hardware Revision A1 using firmware v3.17 or older (2) Authenticated remote command execution (1) unauthenticated vulnerabilities. Since this product shares firmware with other models in the DSR Family, DSR-150 / DSR-250 / DSR-500 / DSR-1000AC will require updates to patch these issues. The two vulnerabilities were confirmed, and patches are under development. One of the reported vulnerabilities is how the device functionally works, and D-Link will not correct it on this generation of products.


3rd Party Report information

 

Report provided :: Digital Defense, Inc. Vulnerability Research Team :: LINK

                     Coordination: Samuel Shapiro:: VulnerabilityResearch _at_ digitaldefense _dot_ com

 

Report :

   

Issue 1: Unauthenticated Remote LAN/WAN Root Command Injection

 

Impact: Unauthenticated users with access to the "Unified Services Router" web interface, either on LAN or WAN, can inject arbitrary commands via crafted requests, which will be executed with root privileges.

 

 Details: The following lua cgi actions, which are accessible without authentication, execute a lua library function which passes user-supplied data to a call to os.popen() as part of a command intended to calculate a hash: /platform.cgi?action=duaAuth, /platform.cgi?action=duaLogout

 

Fix: Under Development Estimated Release Mid-December 2020 

   

Issue 2: Authenticated Root Command Injection

   

Impact: Authenticated users with access to the "Unified Services Router" web interface, either on LAN or WAN, can inject arbitrary commands via crafted requests, which will be executed with root privileges.

 

 Details: The Lua CGI, which handles requests from the "Package Management" form in the "Unified Services Router" web interface, has no server-side filtering for the multi-part POST parameters payload, which are passed to os. execute () functions intended to move the uploaded file to another directory.

 

Fix: Under Development Estimated Release Mid-December 2020  

 

Issue 3: Authenticated Crontab Injection

 

Impact: Authenticated users with access to the "Unified Services Router" web interface, either on LAN or WAN, can inject arbitrary CRON entries, which will be executed as root by modifying a downloaded router configuration file, updating the CRC, and reuploading the resulting crafted configuration file.

 

Details: The configuration file's mechanism is authenticated upon upload is trivially bypassed by a malicious user creating a crafted configuration file that adds new cron entries to execute arbitrary commands as root. 

 

Response: D-Link declined recognition of this report. For this generation of product, the device uses a plain text config, which is the design to directly edit and upload the config to the same DSR devices accordingly. If D-Link mitigates issue #1 and #2, as well as other, recently reported issues, the malicious user would need to engineer a way of gaining access to the device to upload a configuration file, so we understand the report but classify the report as low-threat once the patched firmware is available.

 

   

 Affected Models

 

Model

Hardware Revision

Affected FW

Fixed FW

Recommendation

 Last Updated

DSR-150

All Rev. A Hardware Revision

v3.17 & Below

Under Investigation

Pending Family Firmware Patch

11/18/2020

DSR-250

All Rev. A Hardware Revisions

v3.17 & Below

Under Development

Est. Patch Mid-Dec'2020

11/18/2020

DSR-500

All Rev. A Hardware Revision

v3.17 & Below

Under Investigation

Pending Family Firmware Patch

11/18/2020

DSR-1000AC

All Rev. A Hardware Revision

v3.17 & Below

Under Investigation

Pending Family Firmware Patch

11/18/2020

  

Regarding Security patch for your D-Link Devices
 
Firmware updates address the security vulnerabilities in affected D-Link devices. D-Link will update this continually and we strongly recommend all users to install the relevant updates.
 
Please note that this is a device beta software, beta firmware, or hot-fix release which is still undergoing final testing before its official release. The beta software, beta firmware, or hot-fix is provided on an “as is” and “as available” basis and the user assumes all risk and liability for use thereof. D-Link does not provide any warranties, whether express or implied, as to the suitability or usability of the beta firmware. D-Link will not be liable for any loss, whether such loss is direct, indirect, special or consequential, suffered by any party as a result of their use of the beta firmware.
 
As there are different hardware revisions on our products, please check this on your device before downloading the correct corresponding firmware update. The hardware revision information can usually be found on the product label on the underside of the product next to the serial number. Alternatively, they can also be found on the device web configuration.