CVE-2026-42372: D-Link DIR-605L A1 Hardcoded Telnet Backdoor Credentials
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 "wrgn35dlwbrdir605l" read from /etc/alphaconfig/imagesign. 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.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-42372?
CVE-2026-42372 is considered a high severity vulnerability due to the presence of hardcoded telnet backdoor credentials.
How do I fix CVE-2026-42372?
To mitigate CVE-2026-42372, it is recommended to disable the telnet service if it is not needed or to upgrade to a newer model that does not have this vulnerability.
What devices are affected by CVE-2026-42372?
CVE-2026-42372 specifically affects the D-Link DIR-605L hardware revision A1 model.
What is the nature of the vulnerability in CVE-2026-42372?
The vulnerability in CVE-2026-42372 is a hardcoded telnet backdoor that allows unauthorized access to the device.
Is D-Link DIR-605L hardware revision A1 still supported due to CVE-2026-42372?
D-Link DIR-605L hardware revision A1 is categorized as End-of-Life (EOL) and is no longer supported.