Source: vulnreport@tenable.com
Netgear Nighthawk R6700 version 1.0.4.120 makes use of a hardcoded credential. It does not appear that normal users are intended to be able to manipulate configuration backups due to the fact that they are encrypted/obfuscated. By extracting the configuration using readily available public tools, a user can reconfigure settings not intended to be manipulated, repackage the configuration, and restore a backup causing these settings to be changed.
Netgear Nighthawk R6700 routers are vulnerable to a critical security flaw due to a hardcoded credential within the device's firmware. This allows attackers to extract, modify, and restore configuration backups, potentially leading to complete device compromise, including network access and data exfiltration.
Step 1: Configuration Extraction: An attacker obtains the configuration backup file from the vulnerable Netgear R6700 router using readily available tools or techniques. This could involve exploiting other vulnerabilities, social engineering, or direct access to the device's management interface.
Step 2: Decryption/De-obfuscation: The attacker uses the hardcoded credential to decrypt or de-obfuscate the configuration backup file. This reveals the router's settings in a readable format.
Step 3: Configuration Modification: The attacker modifies the configuration file to include malicious settings. This could involve changing DNS servers, enabling remote access, or creating new administrative accounts.
Step 4: Configuration Repackaging: The attacker repackages the modified configuration file, potentially re-encrypting it if necessary, using the same hardcoded credential.
Step 5: Configuration Restoration: The attacker uploads and restores the modified configuration backup to the vulnerable Netgear R6700 router. The router, lacking proper validation, applies the malicious settings, granting the attacker control.
The vulnerability stems from the use of a hardcoded credential within the Netgear R6700 firmware. This credential is used to encrypt and decrypt configuration backups. While the backups are obfuscated, the use of a predictable, hardcoded key allows attackers to reverse engineer the encryption. The flaw lies in the lack of proper access controls and authentication mechanisms for configuration management. Specifically, the firmware fails to adequately validate the integrity of restored configuration files, allowing attackers to inject malicious settings. The root cause is the insecure design choice of using a static, easily discoverable key for sensitive operations, combined with insufficient input validation during the configuration restore process. This allows for the manipulation of settings not intended for user modification, leading to potential network compromise.
While no specific APTs are definitively linked, this vulnerability is attractive to a wide range of threat actors due to its potential for widespread network compromise. It is likely that both state-sponsored actors and financially motivated cybercriminals would exploit this vulnerability. The vulnerability is not listed on the CISA KEV at the time of this report, but given its severity, it is a strong candidate for future inclusion.
Monitor network traffic for unusual outbound connections from the router, especially to suspicious IP addresses or domains.
Analyze router configuration backups for unauthorized modifications, such as changes to DNS settings, firewall rules, or administrative accounts.
Examine router logs for suspicious activity, including failed login attempts, configuration changes, and unusual network behavior.
Implement network intrusion detection systems (IDS) to identify and alert on known exploit attempts or malicious traffic patterns.
Monitor for the presence of known malicious domains or IP addresses in the router's DNS configuration.
Upgrade the Netgear R6700 firmware to the latest available version, which addresses the hardcoded credential issue.
If upgrading is not immediately possible, consider isolating the router from the internet by placing it behind a firewall or using a VPN.
Change the default administrative password to a strong, unique password.
Disable remote management access to the router if not required.
Regularly review router logs for suspicious activity.
Implement a network segmentation strategy to limit the impact of a compromised router.
Consider replacing the vulnerable device with a more secure router.