CVE-2021-45548 in D7800
Summary
by MITRE • 12/26/2021
Certain NETGEAR devices are affected by command injection by an authenticated user. This affects D7800 before 1.0.1.60, DM200 before 1.0.0.66, EX2700 before 1.0.1.56, EX6150v2 before 1.0.1.86, EX6200v2 before 1.0.1.86, EX6250 before 1.0.0.128, EX6400 before 1.0.2.144, EX6400v2 before 1.0.0.128, EX6410 before 1.0.0.128, EX6420 before 1.0.0.128, EX7300 before 1.0.2.144, EX7300v2 before 1.0.0.128, EX7320 before 1.0.0.128, R7500v2 before 1.0.3.46, R7800 before 1.0.2.74, R8900 before 1.0.5.26, R9000 before 1.0.5.2, RAX120 before 1.0.1.128, WN3000RPv2 before 1.0.0.78, WN3000RPv3 before 1.0.2.80, WNR2000v5 before 1.0.0.74, XR500 before 2.3.2.66, RBK20 before 2.7.3.22, RBR20 before 2.7.3.22, RBS20 before 2.7.3.22, RBK40 before 2.7.3.22, RBR40 before 2.7.3.22, and RBS40 before 2.7.3.22.
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Analysis
by VulDB Data Team • 12/28/2021
This vulnerability represents a critical command injection flaw in NETGEAR networking equipment that allows authenticated attackers to execute arbitrary commands on affected devices. The vulnerability stems from insufficient input validation and sanitization within the web interface of these routers and wireless access points, creating a pathway for malicious users who have already established authentication credentials to escalate their privileges and gain unauthorized system access. The affected devices span multiple product lines including routers, wireless access points, and mesh networking systems, indicating a widespread issue that impacts both consumer and small business networking equipment. This vulnerability falls under the Common Weakness Enumeration category CWE-77 which specifically addresses command injection flaws in software applications that handle user input without proper validation or sanitization.
The technical implementation of this vulnerability occurs through the web-based administration interface where user-supplied parameters are directly incorporated into system commands without adequate filtering or escaping mechanisms. When an authenticated user submits malicious input through web forms or API endpoints, the system processes these inputs without proper sanitization, allowing attackers to inject operating system commands that execute with the privileges of the web server process. This creates a significant risk because the web server typically runs with elevated privileges necessary to manage network configurations and system functions. The vulnerability affects devices from various generations and models, suggesting that the underlying flaw exists in the firmware development practices rather than being isolated to specific product lines or release versions.
The operational impact of this vulnerability is substantial as it provides attackers with full control over affected devices, enabling them to modify network configurations, redirect traffic, steal sensitive information, or use the devices as entry points for further network infiltration. An authenticated attacker with access to the device's web interface can leverage this vulnerability to execute commands that may include disabling security features, modifying firewall rules, installing malware, or establishing persistent backdoors. The attack surface extends beyond individual device compromise to potentially enable lateral movement within corporate networks where these devices serve as network gateways or access points. This aligns with ATT&CK technique T1059.001 for command and scripting interpreter and T1068 for exploit for privilege escalation, making it a particularly dangerous vulnerability for network infrastructure.
Mitigation strategies should focus on immediate firmware updates from NETGEAR to address the command injection vulnerability, as well as implementing network segmentation and access controls to limit the potential impact of compromised devices. Organizations should also consider monitoring network traffic for unusual patterns that might indicate exploitation attempts, particularly around web interface access and system command execution. Network administrators should enforce strong authentication practices, including multi-factor authentication where possible, and regularly audit device configurations to detect unauthorized changes. The vulnerability highlights the importance of proper input validation and the principle of least privilege in embedded system development, where device firmware should never trust user input and should always sanitize all parameters before processing. Additionally, organizations should implement network monitoring solutions that can detect anomalous command execution patterns and maintain up-to-date vulnerability assessments to identify other potential weaknesses in their networking infrastructure.