CVE-2019-20724 in D3600
Summary
by MITRE
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects D3600 before 1.0.0.75, D6000 before 1.0.0.75, D6100 before 1.0.0.63, D7800 before 1.0.1.44, R7500v2 before 1.0.3.38, R7800 before 1.0.2.52, R8900 before 1.0.4.2, R9000 before 1.0.4.2, RBK20 before 2.3.0.28, RBR20 before 2.3.0.28, RBS20 before 2.3.0.28, RBK50 before 2.3.0.32, RBR50 before 2.3.0.32, RBS50 before 2.3.0.32, RBS40 before 2.3.0.28, WNDR3700v4 before 1.0.2.102, WNDR4300v1 before 1.0.2.104, WNDR4300v2 before 1.0.0.58, WNDR4500v3 before 1.0.0.58, WNR2000v5 before 1.0.0.68, and XR500 before 2.3.2.32.
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Analysis
by VulDB Data Team • 05/31/2024
This vulnerability represents a critical command injection flaw in NETGEAR networking equipment that allows authenticated users to execute arbitrary commands on affected devices. The issue stems from insufficient input validation within the web interface of these routers and wireless access points, creating a pathway for malicious actors who have already gained legitimate credentials to escalate their privileges and compromise the entire network infrastructure. The affected devices span multiple product lines including routers, wireless access points, and network bridges, indicating a widespread vulnerability that impacts both consumer and enterprise-grade networking equipment.
The technical implementation of this flaw involves the improper handling of user-supplied input in web-based management interfaces, where command-line arguments are directly concatenated into system execution calls without adequate sanitization or escaping mechanisms. This pattern aligns with common CWE-77 (Improper Neutralization of Special Elements used in a Command) and CWE-94 (Improper Control of Generation of Code) classifications, which are fundamental to command injection vulnerabilities. Attackers can leverage this weakness by crafting specially formatted input parameters that, when processed by the affected software, result in unintended system command execution rather than the intended web interface functionality.
From an operational perspective, the impact extends far beyond simple unauthorized access, as authenticated command injection provides attackers with complete control over affected devices. This capability enables network reconnaissance, port scanning, and potential lateral movement within the network infrastructure. The vulnerability is particularly concerning because it affects devices that typically operate in residential and small office environments where network segmentation may be minimal, allowing attackers to pivot from compromised devices to access connected systems and sensitive network resources. The affected product versions suggest this vulnerability has persisted across multiple firmware releases, indicating inadequate security testing or patch management processes within NETGEAR's development lifecycle.
The attack surface for this vulnerability encompasses any authenticated user who can access the device's web management interface, which typically requires valid username and password credentials. This authentication requirement reduces the attack vector compared to unauthenticated vulnerabilities but does not eliminate the risk, as credentials can be obtained through various means including credential stuffing, phishing attacks, or exploitation of other vulnerabilities in the network ecosystem. The affected device list includes both older and newer models, suggesting that NETGEAR may have failed to adequately address this fundamental security flaw across their product portfolio, potentially indicating deeper architectural issues in their security development practices.
Mitigation strategies should prioritize immediate firmware updates from NETGEAR to address the identified command injection vulnerability, as these patches typically include proper input validation and sanitization mechanisms to prevent command concatenation attacks. Network segmentation and access control measures should be implemented to limit the potential impact of compromised devices, including restricting administrative access to authorized personnel only and implementing strong authentication mechanisms such as multi-factor authentication. Security monitoring should include detection of unusual command execution patterns and unauthorized configuration changes, while regular vulnerability assessments should be conducted to identify and remediate similar security flaws in network infrastructure components. Organizations should also consider implementing network access control policies that limit the scope of impact from compromised devices and establish incident response procedures for handling potential command injection exploits.