CVE-2021-45555 in R7900P
Summary
by MITRE • 12/26/2021
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects R7900P before 1.4.2.84, R7960P before 1.4.2.84, and R8000P before 1.4.2.84.
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Analysis
by VulDB Data Team • 12/28/2021
This vulnerability represents a critical command injection flaw in NETGEAR routers that allows authenticated users to execute arbitrary commands on affected devices. The issue affects specific models including the R7900P, R7960P, and R8000P routers, all prior to firmware version 1.4.2.84. The vulnerability stems from insufficient input validation and sanitization within the web interface authentication handling mechanisms, creating an opportunity for privilege escalation and remote code execution. The flaw specifically manifests when authenticated users submit malicious input through web forms or API endpoints that are not properly sanitized before being processed by the underlying system commands.
The technical implementation of this vulnerability involves the improper handling of user-supplied input within the router's web management interface. When an authenticated user submits data through specific parameters, the system fails to adequately validate or sanitize the input before incorporating it into system command executions. This creates a classic command injection scenario where attacker-controlled input can be interpreted and executed as shell commands by the router's operating system. The vulnerability is particularly concerning because it requires only authentication, which is typically accessible to users within the local network, making exploitation relatively straightforward for attackers with network access.
From an operational impact perspective, this vulnerability exposes affected NETGEAR routers to significant security risks including full system compromise, data exfiltration, and potential lateral movement within network environments. An attacker who gains access to a local network and can authenticate to the router's web interface can execute arbitrary commands with the privileges of the web server process, potentially leading to complete device takeover. The vulnerability affects enterprise and residential network environments alike, with implications for network security posture and compliance requirements. Organizations using these affected router models face risks of unauthorized access to network resources, potential data breaches, and disruption of network services. The impact extends beyond individual device compromise to potential supply chain vulnerabilities if these devices are part of larger network infrastructures.
The vulnerability aligns with CWE-77 and CWE-89 which specifically address command injection flaws in software systems. From the MITRE ATT&CK framework perspective, this vulnerability maps to techniques such as T1059.001 (Command and Scripting Interpreter: PowerShell) and T1068 (Exploitation for Privilege Escalation) as attackers can leverage the authenticated access to escalate privileges and execute arbitrary commands. Network administrators should immediately implement firmware updates to version 1.4.2.84 or later for all affected R7900P, R7960P, and R8000P models. Additionally, network segmentation, firewall rule enforcement, and monitoring of web interface access should be implemented to limit potential exploitation. Regular vulnerability assessments and network scanning should be conducted to identify any remaining instances of affected devices within the network infrastructure.