Netgear DGN Devices Remote Code Execution Scanner

Netgear DGN Devices are a series of networking products widely used for home and small business internet connectivity. These devices offer advanced routing and security functionalities, allowing users to manage their networks efficiently. They provide essential features such as firewall configurations, port forwarding, and remote administration. Due to their widespread adoption, security vulnerabilities in these devices can have a significant impact. Many organizations and individuals rely on Netgear DGN Devices for seamless network access. Ensuring their security is critical to prevent unauthorized access and potential data breaches.

This scanner identifies a critical remote code execution (RCE) vulnerability in Netgear DGN Devices. The vulnerability allows unauthenticated attackers to bypass security mechanisms and execute arbitrary commands with root privileges. Attackers can exploit this flaw by sending specially crafted HTTP requests to the affected device. Successful exploitation grants full control over the device, allowing adversaries to manipulate network settings, exfiltrate data, or launch further attacks. Given the severity of this vulnerability, immediate mitigation is necessary to prevent unauthorized access. Proper security measures must be implemented to protect against potential exploits.

The vulnerability resides in the setup.cgi endpoint of the Netgear DGN Devices. Attackers can craft a request that includes a malicious command in the 'cmd' parameter, allowing arbitrary command execution. This occurs due to improper input validation, which fails to sanitize user-supplied input. When exploited, the attacker can execute commands remotely with the highest level of privileges, leading to full system compromise. The scanner sends a test request with a randomized string and verifies the presence of the expected output in the response. This method ensures accurate detection while minimizing false positives.

Exploitation of this vulnerability can result in severe security implications. Attackers can take full control of the affected device, modifying network configurations and potentially intercepting sensitive data. Malicious actors could use compromised devices as a launch point for further attacks within the network. Unauthorized access to router settings may allow attackers to change DNS configurations, leading to phishing attacks. Additionally, attackers may install persistent malware, making it difficult to remove unauthorized access. Immediate mitigation, including firmware updates and access control restrictions, is essential to prevent exploitation.

REFERENCES

• https://www.crowdsec.net/blog/netgear-rce-and-how-vulnerabilities-persist-in-the-wild
• https://github.com/rapid7/metasploit-framework/blob/master/documentation/modules/exploit/linux/http/netgear_dgn1000_setup_unauth_exec.md