CVE-2018-21103 in R7800
Summary
by MITRE
NETGEAR R7800 devices before 1.0.2.60 are affected by command injection by an authenticated user.
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Analysis
by VulDB Data Team • 06/02/2024
The vulnerability identified as CVE-2018-21103 affects NETGEAR R7800 wireless routers running firmware versions prior to 1.0.2.60, representing a critical command injection flaw that allows authenticated attackers to execute arbitrary commands on the affected devices. This vulnerability falls under the CWE-77 category, which specifically addresses command injection vulnerabilities where untrusted data is incorporated into system commands without proper sanitization or validation. The affected device model represents a high-end consumer-grade router that typically serves as a central networking hub for residential and small office environments, making it a potentially attractive target for cybercriminals seeking persistent access to network infrastructure.
The technical exploitation of this vulnerability occurs through authenticated user sessions, meaning that an attacker must first establish valid credentials to compromise the device. The flaw manifests when the device fails to properly sanitize user-supplied input in specific parameters, allowing maliciously crafted commands to be executed within the context of the router's operating system. This type of vulnerability enables attackers to gain root-level access to the device, potentially allowing them to modify network configurations, install malicious software, or use the device as a pivot point for attacking other systems within the local network. The command injection occurs in the web interface handling of the router's management system, where user inputs are directly concatenated into system commands without adequate filtering or escaping mechanisms.
The operational impact of this vulnerability extends beyond simple unauthorized access, as it provides attackers with complete control over the affected router's functionality and network traffic management capabilities. Network administrators may lose visibility into their network traffic, as attackers can potentially redirect or monitor data flows through the compromised device. The vulnerability also poses significant risks to network security posture, as routers often serve as the first line of defense in network security architectures. Attackers could leverage this access to modify firewall rules, disable security features, or establish persistent backdoors that could remain undetected for extended periods. The compromised device could also be used to launch attacks against other systems on the network or serve as a staging point for broader network infiltration activities.
Mitigation strategies for this vulnerability primarily focus on immediate firmware updates to version 1.0.2.60 or later, which contain patches that properly sanitize input parameters and prevent command injection attacks. Network administrators should also implement additional security controls including regular monitoring of router configurations, implementing network segmentation to limit the impact of potential compromises, and establishing robust access control policies for router management interfaces. The vulnerability demonstrates the importance of secure coding practices and input validation, as outlined in the OWASP Top Ten and NIST cybersecurity frameworks. Organizations should also consider implementing network intrusion detection systems to monitor for suspicious activities that might indicate exploitation attempts, and maintain detailed logs of router configuration changes to detect unauthorized modifications. Regular security assessments and vulnerability scanning of network infrastructure remain essential practices to identify and remediate similar vulnerabilities before they can be exploited by malicious actors.