CVE-2019-19823 Scanner

These routers, commonly used for residential and small business networking, are produced by TOTOLINK and utilize Realtek SDK firmware for network management. Networking professionals, IT administrators, and home users typically deploy these devices due to their affordability and basic configuration capabilities. Their primary use is to provide internet connectivity and local network management among connected devices. The popularity of these routers is due to their relative ease of setup and operation for non-expert users. The routers offer standard security features but may become susceptible to vulnerabilities when default configurations are left unchanged. Understanding the risk of this device is vital for maintaining network security and preventing unauthorized access.

The vulnerability present in the TOTOLINK/Realtek routers can result in unauthorized data disclosure. Remote attackers could potentially exploit this flaw to access sensitive information, including configuration settings and credentials, without authorization. Failure to address such vulnerabilities could lead to network interception or further attacks. This flaw primarily arises due to the insecure default settings in the router's firmware, specifically concerning access to the "config.dat" file. An attacker only requires network access to attempt an exploitation, which could compromise the entire network's security. Identifying these risks highlights the importance of updating firmware and configuring routers securely.

Technically, the vulnerability exists because accessible endpoints such as "/config.dat" expose sensitive data, which should typically require proper authentication. In these routers, the absence of checks allows unprotected downloads of configuration files. The exploitation involves sending a straightforward HTTP GET request to retrieve this configuration. Critical indicators include HTTP responses containing plain-text configurations and server information as "boa." The presence of these markers signifies that the accessed data includes sensitive router settings. The vulnerability consequently lies in both the insecure implementation of configuration file access and insufficient validation mechanisms.

Once exploited, this vulnerability could significantly impact the network's security posture. Attackers gaining access to the router's configuration can lead to unauthorized modifications, exposure of network details, and potential downstream attacks. Such exposures form a stepping stone to intercept data packets or deploy threat vectors across a compromised network. The risk extends to potential service disruptions and device misconfigurations, affecting both functionality and security. Proactively addressing these issues can prevent unauthorized data access and fortify the network against adversaries.

REFERENCES

• http://packetstormsecurity.com/files/156083/Realtek-SDK-Information-Disclosure-Code-Execution.html
• https://nvd.nist.gov/vuln/detail/CVE-2019-19822