CVE-2026-42373 (GCVE-0-2026-42373)
Vulnerability from cvelistv5 – Published: 2026-05-04 15:57 – Updated: 2026-05-04 16:34 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)
CWE
- CWE-798 - Use of Hard-coded Credentials
Assigner
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| D-Link | DIR-605L Firmware |
Affected:
B2
(custom)
cpe:2.3:o:dlink:dir-605l_firmware:*:*:*:*:*:*:*:* |
Date Public ?
2026-04-24 00:00
Credits
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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