D-Link DIR 823 Vulnerabilities & CVEs

Q: Is my D-Link DIR 823 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.

Q: How do I update my D-Link DIR 823'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.

Q: 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No — ProbeShield scans your network and tells you what it finds (open ports, default credentials, outdated firmware signals) so you know what to fix, and how.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.

Known CVEs

CVE-2016-5681CRITICAL (9.8)

Stack-based buffer overflow in dws/api/Login on D-Link DIR-850L B1 2.07 before 2.07WWB05, DIR-817 Ax, DIR-818LW Bx before 2.05b03beta03, DIR-822 C1 3.01 before 3.01WWb02, DIR-823 A1 1.00 before 1.00WWb05, DIR-895L A1 ...

Affected: versions <= 1.00Fixed in: later than 1.00

CVE-2016-6563CRITICAL (9.8)

Processing malformed SOAP messages when performing the HNAP Login action causes a buffer overflow in the stack in some D-Link DIR routers. The vulnerable XML fields within the SOAP body are: Action, Username, LoginPas...

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

CVE-2019-17621CRITICAL (9.8)CISA KEV

The UPnP endpoint URL /gena.cgi in the D-Link DIR-859 Wi-Fi router 1.05 and 1.06B01 Beta01 allows an Unauthenticated remote attacker to execute system commands as root, by sending a specially crafted HTTP SUBSCRIBE re...

Affected: versions <= 1.00b06Fixed in: later than 1.00b06

CVE-2019-20213HIGH (7.5)

D-Link DIR-859 routers before v1.07b03_beta allow Unauthenticated Information Disclosure via the AUTHORIZED_GROUP=1%0a value, as demonstrated by vpnconfig.php.

Affected: versions <= 1.00b06Fixed in: later than 1.00b06

CVE-2024-27660MEDIUM (6.5)

D-Link DIR-823G A1V1.0.2B05 was discovered to contain a Null-pointer dereferences in sub_41C488(). This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted input.

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 823 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 823'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.