CVE-2026-42373 (GCVE-0-2026-42373)

Vulnerability from cvelistv5 – Published: 2026-05-04 15:57 – Updated: 2026-05-05 12:43 Unsupported When Assigned
VLAI
Title
D-Link DIR-605L B2 Hardcoded Telnet Backdoor Credentials
Summary
D-Link DIR-605L Hardware Revision B2 (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 "wrgn76_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.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-05 03:56 UTC
CWE
  • CWE-798 - Use of Hard-coded Credentials
Assigner
securin CNA under the mitre root
CNA scorecard B 80/100 over 71 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
D-Link DIR-605L Firmware Affected: B2 (custom)
    cpe:2.3:o:dlink:dir-605l_firmware:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-04-24 00:00
Credits
Arjun Basnet from Securin Labs
Show details on NVD website
To clipboard 

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