Actively exploited vulnerability

D-Link Multiple Routers: code execution flaw under attack

CVE-2021-45382 · D-Link Multiple Routers Remote Code Execution Vulnerability

Home network device9.8 critical

What is affected

D-Link Multiple Routers are the kind of equipment many homes and small offices run for years without touching: a router, camera or storage box. Attackers scan the internet for exposed units, and a hijacked one can spy on traffic or be enrolled in a botnet without any visible sign.

A remote code execution vulnerability exists in all series H/W revisions routers via the DDNS function in ncc2 binary file.

CISA's description

What an attacker can do

This is a code execution flaw. It lets an attacker run their own commands or programs on the affected system. In practice that usually means taking it over: installing malware, stealing data or using it to reach other devices on the same network.

How it is reached
Over the internet or network
Access the attacker needs
No account needed
Does the victim have to do something?
No, works without the victim doing anything

What to do

  1. Check whether you own this device: look at the label on your router, camera or NAS, or open its admin page and note the model and firmware version.
  2. Install the latest firmware from the manufacturer's support page or the device's own update menu.
  3. If the manufacturer no longer releases updates for the model, replace it. An end-of-life device with an exploited flaw cannot be made safe.
  4. Turn off remote administration from the internet unless you truly need it, and change the default admin password.

The impacted product is end-of-life and should be disconnected if still in use.

Action required by CISA for US federal agencies

How urgent is it

CISA added this vulnerability to its Known Exploited Vulnerabilities catalogue on April 4, 2022, which means there is reliable evidence of attacks in the wild. US federal agencies must fix it by April 25, 2022, a deadline that has already passed. That deadline does not bind anyone else, but it shows how seriously the agency rates it.

The EPSS model estimates a 98% probability that this flaw will be exploited somewhere in the next 30 days. That is higher than 99.9% of all scored vulnerabilities.

Its CVSS severity score is 9.8 out of 10 (critical), as recorded in the US National Vulnerability Database.

Technical description

A Remote Command Execution (RCE) vulnerability exists in all series H/W revisions D-link DIR-810L, DIR-820L/LW, DIR-826L, DIR-830L, and DIR-836L routers via the DDNS function in ncc2 binary file. Note: DIR-810L, DIR-820L, DIR-830L, DIR-826L, DIR-836L, all hardware revisions, have reached their End of Life ("EOL") /End of Service Life ("EOS") Life-Cycle and as such this issue will not be patched.

NIST National Vulnerability Database
5,442 members already hereReading, writing, commenting and voting. 0 verified · 167 joined this year