CVE-2017-14421 Explained : Impact and Mitigation

Devices with the D-Link DIR-850L REV. B model and firmware up to FW208WWb02 have a pre-set password for the Alphanetworks account, enabling remote attackers to gain root access through a TELNET session.

Understanding CVE-2017-14421

This CVE identifies a hardcoded password vulnerability in D-Link DIR-850L REV. B devices.

What is CVE-2017-14421?

The vulnerability allows remote attackers to obtain root access via TELNET due to a hardcoded password in the Alphanetworks account.

The Impact of CVE-2017-14421

Remote attackers can gain unauthorized root access to affected devices.
Security compromise and potential data breaches are possible.

Technical Details of CVE-2017-14421

The technical aspects of the vulnerability are as follows:

Vulnerability Description

D-Link DIR-850L REV. B devices have a hardcoded password for the Alphanetworks account.

Affected Systems and Versions

Product: D-Link DIR-850L REV. B
Firmware: Up to FW208WWb02

Exploitation Mechanism

Attackers can exploit the vulnerability by accessing the hardcoded password after a device reset, allowing root access via TELNET.

Mitigation and Prevention

Steps to address the CVE-2017-14421 vulnerability:

Immediate Steps to Take

Change the default password immediately.
Disable remote management if not required.
Update the firmware to the latest version.

Long-Term Security Practices

Regularly change passwords for all accounts.
Implement network segmentation to limit access.
Conduct security audits and penetration testing.

Patching and Updates

Apply patches and firmware updates provided by D-Link to address the hardcoded password vulnerability.