VULNERABILITY INTELLIGENCE
CVE-2026-42374
CVSS score9.8 CRITICAL
EPSS probability0.47%
CISA KEVNot currently listed
Published2026-05-04
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Description
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.
Weakness classification
- 33c584b5-0579-4c06-b2a0-8d8329fcab9c: CWE-798
Primary references
- 33c584b5-0579-4c06-b2a0-8d8329fcab9c — Exploit, Third Party Advisory
- 134c704f-9b21-4f2e-91b3-4a467353bcc0 — Exploit, Third Party Advisory