Search criteria
2 vulnerabilities found for DIR-456U Firmware by D-Link
CVE-2026-42376 (GCVE-0-2026-42376)
Vulnerability from nvd – Published: 2026-05-04 16:03 – Updated: 2026-05-04 16:32 Unsupported When Assigned
VLAI?
Title
D-Link DIR-456U A1 Hardcoded Telnet Backdoor Credentials
Summary
D-Link DIR-456U Hardware Revision A1 (End-of-Life, EOL) contains a hardcoded telnet backdoor. The device starts a telnet daemon at boot via /etc/init0.d/S80telnetd.sh with the username "Alphanetworks" and the static password "whdrv01_dlob_dir456U" read from /etc/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)
CWE
- CWE-798 - Use of Hard-coded Credentials
Assigner
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| D-Link | DIR-456U Firmware |
Affected:
A1
(custom)
cpe:2.3:o:dlink:dir-456u_firmware:*:*:*:*:*:*:*:* |
Date Public ?
2026-04-24 00:00
Credits
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CVE-2026-42376 (GCVE-0-2026-42376)
Vulnerability from cvelistv5 – Published: 2026-05-04 16:03 – Updated: 2026-05-04 16:32 Unsupported When Assigned
VLAI?
Title
D-Link DIR-456U A1 Hardcoded Telnet Backdoor Credentials
Summary
D-Link DIR-456U Hardware Revision A1 (End-of-Life, EOL) contains a hardcoded telnet backdoor. The device starts a telnet daemon at boot via /etc/init0.d/S80telnetd.sh with the username "Alphanetworks" and the static password "whdrv01_dlob_dir456U" read from /etc/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)
CWE
- CWE-798 - Use of Hard-coded Credentials
Assigner
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| D-Link | DIR-456U Firmware |
Affected:
A1
(custom)
cpe:2.3:o:dlink:dir-456u_firmware:*:*:*:*:*:*:*:* |
Date Public ?
2026-04-24 00:00
Credits
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