CVE-2018-21152 in D7800
Summary
by MITRE
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects D7800 before 1.0.1.34, R7500v2 before 1.0.3.26, R7800 before 1.0.2.42, R8900 before 1.0.3.10, R9000 before 1.0.3.10, WNDR4300v2 before 1.0.0.54, and WNDR4500v3 before 1.0.0.54.
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Analysis
by VulDB Data Team • 06/03/2024
This vulnerability represents a critical command injection flaw in NETGEAR router firmware that allows authenticated users to execute arbitrary commands on affected devices. The issue stems from improper input validation within the web-based management interface of multiple router models, creating a pathway for privilege escalation through malicious command injection attacks. The affected devices include several popular NETGEAR router models including the D7800, R7500v2, R7800, R8900, R9000, WNDR4300v2, and WNDR4500v3, all of which are vulnerable in specific firmware versions prior to the mentioned patches. The vulnerability exists in the handling of user-supplied input within the device's administrative web interface, where commands are not properly sanitized before being executed by the underlying system shell.
The technical implementation of this flaw allows an authenticated attacker with access to the router's web management interface to inject malicious commands that will be executed with elevated privileges. This creates a significant risk as the attacker can leverage the compromised device to perform actions such as modifying router configurations, accessing network traffic, redirecting connections, or even installing malicious software on the device. The vulnerability specifically impacts the authentication and authorization mechanisms within the web interface, where user input is directly processed without adequate sanitization or validation, enabling the execution of operating system commands through the device's command processing pipeline.
From an operational perspective, this vulnerability presents a substantial security risk to organizations and individuals who rely on NETGEAR routers for network infrastructure. The authenticated nature of the attack means that an attacker must first obtain valid credentials, which is often achievable through social engineering, credential reuse attacks, or exploitation of other vulnerabilities. Once authenticated, the attacker can leverage this command injection vulnerability to gain complete control over the affected router, potentially compromising the entire network segment it serves. This represents a critical weakness in network security infrastructure, as routers are often considered trusted components that should not be vulnerable to command injection attacks that could allow lateral movement or persistent access within a network.
The vulnerability aligns with CWE-77 and CWE-88 within the Common Weakness Enumeration framework, specifically addressing command injection flaws in web applications and input validation issues. This categorization places the vulnerability within the broader context of attack patterns documented in the MITRE ATT&CK framework under techniques such as command and control, privilege escalation, and persistence mechanisms. Network administrators should consider this vulnerability as part of a comprehensive security posture assessment, particularly focusing on the principle of least privilege and the importance of keeping network infrastructure components updated with the latest security patches. The affected firmware versions represent a window of opportunity for attackers to exploit this vulnerability, making prompt patching and firmware updates essential for maintaining network security.
Mitigation strategies should include immediate firmware updates to the latest versions provided by NETGEAR, which address the command injection vulnerability through proper input validation and sanitization. Network segmentation and access controls should be implemented to limit access to router management interfaces, ensuring that only authorized personnel can access administrative functions. Additional monitoring and logging of router management activities can help detect potential exploitation attempts, while regular security assessments should verify that all network devices are running patched firmware versions. The vulnerability serves as a reminder of the critical importance of maintaining up-to-date network infrastructure and the potential consequences of failing to apply security patches in a timely manner.