CVE-2018-1144 in N750
Summary
by MITRE
A remote unauthenticated user can execute commands as root in the Belkin N750 using firmware version 1.10.22 by sending a crafted HTTP request to proxy.cgi.
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Analysis
by VulDB Data Team • 01/30/2020
The Belkin N750 wireless router represents a critical security vulnerability in the form of a remote command execution flaw that affects firmware version 1.10.22 and potentially other versions within the same release cycle. This vulnerability resides in the web interface component of the device, specifically in the proxy.cgi script which handles HTTP requests from remote clients. The flaw allows an attacker to execute arbitrary commands with root privileges without requiring any authentication credentials, making it particularly dangerous for network security. The vulnerability stems from insufficient input validation and sanitization within the web application layer, creating an attack surface where user-supplied data can directly influence system command execution.
The technical implementation of this vulnerability involves the manipulation of HTTP request parameters that are processed by the proxy.cgi script. When a remote attacker sends a specially crafted HTTP request to the router's web interface, the system fails to properly validate or sanitize the input parameters before incorporating them into system commands. This classic command injection vulnerability enables the attacker to bypass authentication mechanisms entirely and execute arbitrary shell commands directly on the router's operating system. The vulnerability maps to CWE-77 which describes improper neutralization of special elements used in a command, and more specifically to CWE-94 which addresses the execution of arbitrary code or commands.
The operational impact of this vulnerability extends beyond simple unauthorized access to encompass complete system compromise and potential network infiltration. Once an attacker gains root access to the router, they can modify network configurations, redirect traffic, install malware, or use the device as a pivot point for attacking other systems within the local network. The unauthenticated nature of the attack means that any external party can exploit this vulnerability without needing to know login credentials or having physical access to the device. This makes the vulnerability particularly concerning for enterprise and residential networks where routers are often deployed with default configurations and may be accessible from the internet without proper firewall protection.
Security practitioners should implement immediate mitigations including firmware updates from Belkin to address the command injection vulnerability, network segmentation to isolate critical devices, and proper firewall rules to restrict external access to router management interfaces. The vulnerability demonstrates the importance of input validation and the principle of least privilege in network device security. Organizations should also consider implementing network monitoring solutions to detect anomalous traffic patterns that might indicate exploitation attempts, and regularly audit their network infrastructure for similar vulnerabilities in other network devices. The ATT&CK framework categorizes this type of vulnerability under T1059 for command and scripting interpreter, specifically noting that adversaries may leverage remote access capabilities to execute malicious commands. This vulnerability underscores the critical need for regular security assessments and patch management processes, particularly for network infrastructure devices that are often overlooked in traditional security monitoring programs.