CVE-2026-42374
CriticalSummary
D-Link DIR-600L Hardware Revision B1 contains a hardcoded telnet backdoor. The device starts a telnet daemon at boot with the username 'Alphanetworks' and the static password 'wrgn61_dlwbr_dir600L'.
Risk Assessment
An attacker on the local network can gain root shell access with full administrative control, posing a serious security risk to the organization.
Recommendation
It is recommended to immediately disable the device and replace it with a new model, as the device has reached End-of-Life and will not receive patches.
Original NVD description (English source)
D-Link DIR-600L Hardware Revision B1 (End-of-Life) contains a hardcoded telnet backdoor. The device starts a telnet daemon at boot via /bin/telnetd.sh with the username "Alphanetworks" and the static password "wrgn61_dlwbr_dir600L" read from /etc/alpha_config/image_sign. The custom telnetd binary accepts a -u user:password flag, and the custom login binary uses strcmp() to validate credentials. Successful authentication grants an unauthenticated attacker on the local network a root shell with full administrative control. The device has reached End-of-Life (EOL) and will not receive patches.