Support Announcements
(Non-US) DIR-841 :: FW v3.03 & v3.04 :: Authenticated Command Injection LAN-side Vulnerability




On February 1, 2021, a 3rd party security researcher, submitted a report accusing the (non-US) DIR-841 using firmware v3.03 or v3.04 of a LAN-side authenticated command injection exploit.   The Vulnerability was confirmed and a patch was issued too close the reported issue.  Please find the beta/hotfix release below

3rd Party Report information


          - Report providedVitor Esperança vitorespf _at_ gmail _dot_ com

          - Reference : TBD updaed with Authors Public Disclosure


                 - Using the device with firmware 3.0.3 and 3.0.4, it was possible to inject arbitrary commands when using tools available on the web interface such as: ping and traceroute.


                 - Login in DLINK DIR-841 Web Interface as an admin


                 - Choose the "System" option.


                 - Using the ping or traceroute tool, enter the IP in the interface of the chosen tool, and then immediately
   capture the request using the Burp Suite (proxy tool).


                 - Right after that we can manipulate the host parameter, and insert payloads like:

                 "' & sleep 5'" or " & nc target port '".

                 The sleep command and the nc (netcat) tool will be executed together with the ping / traceroute tool.


 Affected Models


Model Hardware Revision Affected FW Fixed FW Recommendation  Last Updated
DIR-841 All Hardware Revisions v3.0.4 & Below  v3.04 RT819F Hotfix Please Download and Update Device 03/08/2021


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.