CVE-2020-35792 in R7500v2
Summary
by MITRE • 12/30/2020
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects R7500v2 before 1.0.3.48, R8900 before 1.0.5.2, R9000 before 1.0.5.2, and R7800 before 1.0.2.68.
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Analysis
by VulDB Data Team • 12/30/2020
This vulnerability represents a critical command injection flaw that allows authenticated attackers to execute arbitrary commands on affected NETGEAR routers. The issue stems from insufficient input validation and sanitization within the web interface authentication flow, creating a path for privilege escalation through malicious payload injection. Attackers who have already gained access to a legitimate user account can leverage this vulnerability to bypass security controls and gain unauthorized system-level access. The affected models include several popular router series that are widely deployed in both residential and small business environments.
The technical implementation of this vulnerability involves the improper handling of user-supplied parameters within the device management interface, particularly when processing configuration requests or administrative commands. This flaw enables attackers to inject malicious shell commands that get executed with the privileges of the authenticated user account, potentially escalating to root-level access depending on the device architecture and implementation details. The vulnerability is classified as a command injection weakness under CWE-77, which specifically addresses improper validation of system calls in software applications. The attack vector requires an initial authentication presence, making it less severe than unauthenticated attacks but still highly concerning given the privileged nature of router administration.
From an operational perspective, this vulnerability poses significant risks to network security and integrity. Successfully exploited, it allows attackers to modify router configurations, redirect traffic, install malicious firmware, or establish persistent backdoors within the network infrastructure. The impact extends beyond individual devices since these routers typically serve as primary gateways for network access, making them attractive targets for lateral movement attacks within compromised networks. Network administrators should consider this vulnerability as a potential entry point for broader security breaches and should be aware of the implications for their organization's overall security posture.
Mitigation strategies should include immediate firmware updates to versions that address the command injection flaw, particularly for all affected R7500v2, R8900, R9000, and R7800 models. Network segmentation and access control measures can help limit the potential impact of exploitation by restricting administrative access to these devices. Implementing proper network monitoring and anomaly detection systems can aid in identifying suspicious command execution patterns that may indicate exploitation attempts. Additionally, organizations should enforce strong authentication practices including multi-factor authentication for router administration interfaces and regularly review access permissions to minimize the attack surface. The vulnerability also aligns with ATT&CK technique T1059 which covers command and scripting interpreters, highlighting the importance of monitoring for unauthorized command execution within network infrastructure devices.