D-Link DIR-605L Hardware Revision A1 (End-of-Life, EOL) 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 "wrgn35_dlwbr_dir605l" 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.
Description: CWE-798 Use of Hard-coded Credentials
Metrics
Version
Base score
Base severity
Vector
3.1
8.8
HIGH
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Version:3.1
Base score:8.8
Base severity: HIGH
Vector:
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Metrics Other Info
Impacts
CAPEC ID
Description
Solutions
Configurations
Workarounds
This product is End-of-Life and will NOT receive patches. Users should replace the device. Temporary: connect via backdoor and run "killall telnetd" and "iptables -A INPUT -p tcp --dport 23 -j DROP" (lost on reboot).