CVE-2017-18373 in Billion 5200W-T
Summary
by MITRE
The Billion 5200W-T TCLinux Fw $7.3.8.0 v008 130603 router distributed by TrueOnline has three user accounts with default passwords, including two hardcoded service accounts: one with the username true and password true, and another with the username user3 and and a long password consisting of a repetition of the string 0123456789. These accounts can be used to login to the web interface, exploit authenticated command injections, and change router settings for malicious purposes.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 09/11/2023
The CVE-2017-18373 vulnerability affects the Billion 5200W-T TCLinux firmware version 7.3.8.0 v008 130603 router distributed by TrueOnline, representing a critical security flaw that stems from poor credential management practices. This vulnerability exposes three user accounts with default passwords, including two hardcoded service accounts that persist across device deployments. The first account uses the username true with the password true, while the second account employs the username user3 with a password consisting of repeated digits 0123456789. These hardcoded credentials represent a fundamental failure in secure configuration management and demonstrate a lack of proper authentication mechanisms. The vulnerability is classified under CWE-798 as the use of hardcoded credentials, which directly violates security best practices and creates persistent attack vectors.
The technical exploitation of this vulnerability enables unauthorized users to gain authenticated access to the router's web interface through the default accounts. Once authenticated, attackers can leverage these credentials to execute authenticated command injection attacks against the underlying TCLinux operating system. This command injection capability allows for arbitrary code execution with the privileges of the authenticated user, potentially enabling full system compromise. The vulnerability creates a persistent backdoor that remains functional across device reboots and does not require additional exploitation techniques to maintain access. The attack surface is significantly expanded due to the presence of multiple service accounts, providing attackers with alternative access paths if one account is discovered and changed.
The operational impact of CVE-2017-18373 extends beyond simple unauthorized access, as it enables attackers to modify router settings and potentially compromise the entire network infrastructure. The ability to change router configurations creates opportunities for attackers to redirect traffic, disable security features, or establish persistent access points within the network. This vulnerability aligns with ATT&CK technique T1078.004 for valid accounts and T1059.001 for command and scripting interpreter, demonstrating how hardcoded credentials can be leveraged for both initial access and privilege escalation. The vulnerability affects network security by providing attackers with a stable foothold that can be used to conduct further reconnaissance, lateral movement, or data exfiltration activities.
Mitigation strategies for CVE-2017-18373 require immediate action to address the hardcoded credential issue. Network administrators should change the default passwords for all accounts immediately, particularly the service accounts with hardcoded credentials. The router firmware should be updated to the latest available version that addresses this vulnerability, though the specific firmware updates may not be readily available for this older model. Network segmentation and access control measures should be implemented to limit the impact if the vulnerability is exploited. Regular security audits should be conducted to identify other devices with hardcoded credentials, and the vulnerability should be monitored through security advisories and vulnerability management systems. Additionally, implementing network monitoring to detect unauthorized access attempts and command execution activities can help identify exploitation attempts and provide early warning of potential compromise.
The vulnerability demonstrates a critical gap in the security lifecycle of network devices, particularly in the areas of secure configuration and credential management. It highlights the importance of following secure coding practices and implementing proper authentication mechanisms that do not rely on hardcoded credentials. Organizations should implement strict policies for password management and ensure that all default accounts are disabled or have their credentials changed upon device deployment. This vulnerability serves as a reminder of the need for comprehensive security testing during device development and the importance of maintaining up-to-date firmware to address known vulnerabilities. The persistence of such flaws in commercial network equipment underscores the need for continuous security monitoring and proactive vulnerability management across all network infrastructure components.