CVE-2016-0876 in EDR-G903
Summary
by MITRE
Moxa Secure Router EDR-G903 devices before 3.4.12 allow remote attackers to discover cleartext passwords by reading a configuration file.
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Analysis
by VulDB Data Team • 12/22/2018
The CVE-2016-0876 vulnerability affects Moxa Secure Router EDR-G903 devices running firmware versions prior to 3.4.12, representing a critical security flaw that exposes cleartext credentials to remote attackers. This vulnerability stems from improper configuration file handling within the device's firmware implementation, where sensitive authentication information is stored in an unencrypted format within accessible system files. The flaw allows attackers to gain unauthorized access to administrative credentials without requiring any authentication or exploitation of other vulnerabilities, making it particularly dangerous in networked environments where these devices serve as critical infrastructure components.
The technical implementation of this vulnerability involves the device's configuration management system storing password hashes and cleartext credentials in readable files that are accessible through standard network protocols or direct file system access. Attackers can exploit this by simply reading the configuration file through available network interfaces or by physically accessing the device if it is not properly secured. This misconfiguration violates fundamental security principles and represents a failure in proper credential storage practices. The vulnerability aligns with CWE-312 (Cleartext Storage of Sensitive Information) and CWE-259 (Use of Hard-coded Password) categories, demonstrating poor security design practices that expose sensitive data to unauthorized access.
The operational impact of CVE-2016-0876 extends beyond simple credential theft, as compromised administrative access can lead to complete network takeover and persistent backdoor establishment. Attackers can leverage these cleartext credentials to modify device configurations, redirect network traffic, install malicious firmware, or use the device as a pivot point to attack other systems within the network perimeter. This vulnerability particularly affects industrial control systems and network infrastructure where Moxa devices are commonly deployed, potentially enabling sophisticated attacks such as those categorized under ATT&CK technique T1078 (Valid Accounts) and T1566 (Phishing for Information). The exposure of cleartext passwords also enables credential reuse attacks across multiple systems within the organization, amplifying the potential damage.
Organizations should immediately implement firmware updates to version 3.4.12 or later to remediate this vulnerability, while also conducting comprehensive network assessments to identify any potential compromise. Network segmentation and access controls should be strengthened to limit exposure of these devices to untrusted networks. Security monitoring should include detection of unauthorized file access attempts and configuration file reads. Additionally, organizations should implement proper credential management practices, including regular password rotation, use of strong authentication mechanisms, and network access controls to prevent unauthorized access to sensitive configuration files. The vulnerability highlights the importance of secure configuration management and proper credential handling in network infrastructure devices, emphasizing the need for regular security assessments and timely patch management to prevent exploitation of similar flaws in other network components.