CVE-2026-42376

D-Link DIR-456U Hardware Revision A1 End-of-Life, EOL contains a hardcoded telnet backdoor. The device starts a telnet daemon at boot via /etc/init0.d/S80telnetd.sh with the username "Alphanetworks" and the static password "whdrv01dlobdir456U" read from /etc/config/imagesign. The custom telnetd...

CVE-2019-18852

Certain D-Link devices have a hardcoded Alphanetworks user account with TELNET access because of /etc/config/imagesign or /etc/alphaconfig/imagesign. This affects DIR-600 B1 V2.01 for WW, DIR-890L A1 v1.03, DIR-615 J1 v100 for DCN, DIR-645 A1 v1.03, DIR-815 A1 v1.01, DIR-823 A1 v1.01, and DIR-842...

Hardcoded credentials

Certain D-Link devices have a hardcoded Alphanetworks user account with TELNET access because of /etc/config/imagesign or /etc/alphaconfig/imagesign. This affects DIR-600 B1 V2.01 for WW, DIR-890L A1 v1.03, DIR-615 J1 v100 for DCN, DIR-645 A1 v1.03, DIR-815 A1 v1.01, DIR-823 A1 v1.01, and DIR-842...