CVE-2026-42372

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.securin.io/zero-day/cve-2026-42372-hardcoded-telnet-backdoor-in-d-link-dir-605l-a1-end-of-life-	Exploit Third Party Advisory
https://www.securin.io/zero-day/cve-2026-42372-hardcoded-telnet-backdoor-in-d-link-dir-605l-a1-end-of-life-	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:dlink:dir-605l_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:dlink:dir-605l:a1:*:*:*:*:*:*:*

History

26 Oct 2026, 19:10

Type	Values Removed	Values Added
Summary		(es) D-Link DIR-605L Revisión de Hardware A1 (Fin de Vida Útil, EOL) contiene una puerta trasera telnet codificada. El dispositivo inicia un demonio telnet al arrancar a través de /bin/telnetd.sh con el nombre de usuario ’Alphanetworks’ y la contraseña estática ’wrgn35_dlwbr_dir605l’ leída de /etc/alpha_config/image_sign. El binario telnetd personalizado acepta una bandera -u user:password, y el binario de inicio de sesión personalizado usa strcmp() para validar las credenciales. La autenticación exitosa otorga a un atacante no autenticado en la red local un shell de root con control administrativo total. El dispositivo ha alcanzado el Fin de Vida Útil (EOL) y no recibirá parches.

Information

Published : 2026-05-04 17:16

Updated : 2026-10-26 19:10

NVD link : CVE-2026-42372

Mitre link : CVE-2026-42372

CVE.ORG link : CVE-2026-42372

JSON object : View

Products Affected

dlink

dir-605l_firmware
dir-605l

CWE

CWE-798

Use of Hard-coded Credentials

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