D-Link DIR 816 Vulnerabilities & CVEs | ProbeShield

Known CVEs

CVE-2019-10039CRITICAL (9.8)

The D-Link DIR-816 A2 1.11 router only checks the random token when authorizing a goform request. An attacker can get this token from dir_login.asp and use an API URL /goform/setSysAdm to edit the web or system accoun...

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

CVE-2019-10040CRITICAL (9.8)

The D-Link DIR-816 A2 1.11 router only checks the random token when authorizing a goform request. An attacker can get this token from dir_login.asp and use a hidden API URL /goform/SystemCommand to execute a system co...

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

CVE-2019-10041CRITICAL (9.8)

The D-Link DIR-816 A2 1.11 router only checks the random token when authorizing a goform request. An attacker can get this token from dir_login.asp and use an API URL /goform/form2userconfig.cgi to edit the system acc...

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

CVE-2021-26810CRITICAL (9.8)

D-link DIR-816 A2 v1.10 is affected by a remote code injection vulnerability. An HTTP request parameter can be used in command string construction in the handler function of the /goform/dir_setWanWifi, which can lead ...

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

CVE-2021-27113CRITICAL (9.8)

An issue was discovered in D-Link DIR-816 A2 1.10 B05 devices. An HTTP request parameter is used in command string construction within the handler function of the /goform/addRouting route. This could lead to Command I...

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

CVE-2021-27114CRITICAL (9.8)

An issue was discovered in D-Link DIR-816 A2 1.10 B05 devices. Within the handler function of the /goform/addassignment route, a very long text entry for the"'s_ip" and "s_mac" fields could lead to a Stack-Based Buffe...

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

CVE-2021-39509CRITICAL (9.8)

An issue was discovered in D-Link DIR-816 DIR-816A2_FWv1.10CNB05_R1B011D88210 The HTTP request parameter is used in the handler function of /goform/form2userconfig.cgi route, which can construct the user name string t...

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

CVE-2021-39510CRITICAL (9.8)

An issue was discovered in D-Link DIR816_A1_FW101CNB04 750m11ac wireless router, The HTTP request parameter is used in the handler function of /goform/form2userconfig.cgi route, which can construct the user name strin...

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

CVE-2021-31326CRITICAL (9.8)

D-Link DIR-816 A2 1.10 B05 allows unauthenticated attackers to arbitrarily reset the device via a crafted tokenid parameter to /goform/form2Reboot.cgi.

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

CVE-2022-28915CRITICAL (9.8)

D-Link DIR-816 A2_v1.10CNB04 was discovered to contain a command injection vulnerability via the admuser and admpass parameters in /goform/setSysAdm.

Affected: Not version-specific per NVD — check the advisoryFixed in: See vendor advisory

Commonly exposed ports

Port 23 (Telnet) — Sends admin credentials unencrypted — a common target on older router firmware.
Port 80 (HTTP admin panel) — The web admin UI; dangerous if remote/WAN administration is left enabled.
Port 7547 (TR-069 (CWMP)) — ISP remote-management protocol — has been the entry point for several router botnets.
Port 1900 (UPnP/SSDP) — Lets apps on your LAN open firewall holes automatically, sometimes without your knowledge.

Default credentials

From ProbeShield's own tested default-credential list (see probeshield.com/default-passwords/): "admin" / "d-link" or "admin" / "pass" over HTTP.

Hardening checklist

Disable remote (WAN-side) administration unless you specifically need it.
Turn off UPnP unless a specific app you trust requires it.
Turn off WPS — it can let an attacker bypass your Wi-Fi password.
Change the default admin username and password to something unique.
Check for a firmware update in the router’s admin panel and apply it.
Disable Telnet/SSH management access if you don’t actively use it.

Frequently asked questions

Is my D-Link DIR 816 affected by these vulnerabilities? Only if you’re running a firmware version in the affected range listed above and haven’t updated. Check your router's admin panel for its current firmware version and compare it against the ranges below.

How do I update my D-Link DIR 816's firmware? Log into the router's web admin panel (usually at its local IP address) and look for a Firmware Update or System Update section, or use the vendor's mobile app if it has one.

Does ProbeShield fix these vulnerabilities for me? No — ProbeShield scans your network and tells you what it finds (open ports, default credentials, outdated firmware signals) so you know what to fix, and how. It never changes your devices’ settings.

Sources: National Vulnerability Database (NVD), CISA Known Exploited Vulnerabilities Catalog. This page lists which firmware versions are affected — it doesn't claim your specific unit is vulnerable. Check your device's current firmware version in its admin panel and compare it against the ranges above.