What is CVE-2026-42373?

CVE-2026-42373 is a critical-severity vulnerability in D-Link Dir-605l Firmware, classified under Use of Hard-coded Credentials. CVSS score: 9.8/10. Published 2026-05-04.

How severe is CVE-2026-42373?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in D-Link Dir-605l Firmware

CVE-2026-42373

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.

EPSS: 0.005 (39.5th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

CWE-798 — Use of Hard-coded Credentials

References

33c584b5-0579-4c06-b2a0-8d8329fcab9c (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2026-42373?: CVE-2026-42373 is a critical-severity vulnerability in D-Link Dir-605l Firmware, classified under Use of Hard-coded Credentials. CVSS score: 9.8/10. Published 2026-05-04.
How severe is CVE-2026-42373?: Critical severity. CVSS v3 base score is 9.8 out of 10.