CVE-2016-5799 in OnCell
Summary
by MITRE
Moxa OnCell G3100V2 devices before 2.8 and G3111, G3151, G3211, and G3251 devices before 1.7 do not properly restrict authentication attempts, which makes it easier for remote attackers to obtain access via a brute-force attack.
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Analysis
by VulDB Data Team • 09/14/2022
The Moxa OnCell G3100V2 series and related G3111, G3151, G3151, G3121, and G3251 cellular gateway devices present a critical authentication vulnerability that significantly weakens their security posture. These industrial networking devices are designed for remote management and communication in critical infrastructure environments, making their authentication mechanisms crucial for overall system security. The vulnerability stems from insufficient rate limiting and account lockout mechanisms that fail to properly restrict the number of authentication attempts allowed within a given time period.
This weakness creates a pathway for remote attackers to conduct brute-force authentication attacks against the device management interfaces. The lack of proper authentication controls means that malicious actors can systematically try numerous username and password combinations without triggering protective mechanisms that would normally prevent such automated attempts. The vulnerability affects specific firmware versions where the authentication logic does not adequately implement security measures such as account lockout after failed attempts, temporary delays between login attempts, or IP address blocking mechanisms.
The operational impact of this vulnerability extends beyond simple unauthorized access, as these devices often serve as critical communication endpoints in industrial control systems, remote monitoring networks, and cellular backhaul infrastructure. Attackers who successfully exploit this vulnerability can gain full administrative control over the affected devices, potentially leading to complete network compromise, data exfiltration, or disruption of critical communications. The remote nature of the attack means that adversaries do not require physical access or network proximity to exploit the vulnerability, making it particularly dangerous in industrial environments where physical security may be limited.
From a cybersecurity perspective, this vulnerability aligns with CWE-307, which describes improper restriction of repeated operations, and represents a classic example of insufficient account lockout mechanisms. The attack vector falls under the MITRE ATT&CK framework's credential access tactics, specifically targeting the use of brute force methods to compromise authentication systems. Organizations using these devices should immediately implement firmware updates to address the authentication restrictions, while also considering network segmentation and additional monitoring controls to detect potential exploitation attempts. The vulnerability demonstrates the critical importance of robust authentication mechanisms in industrial networking equipment, where the consequences of unauthorized access can extend far beyond traditional enterprise security concerns into operational technology and safety systems.