CVE-2016-6277: High Vulnerability in NETGEAR Multiple Routers

CVE-2016-6277 is a high-severity vulnerability affecting multiple NETGEAR routers, including the R6250, R6400, and R7000 models, among others. The vulnerability allows remote attackers to execute arbitrary commands via shell metacharacters in the path info to cgi-bin/. With a CVSS score of 8.8, this vulnerability poses a significant risk to organizations utilizing these devices. The nature of the vulnerability allows for exploitation over the network, making it particularly concerning for remote attackers.

Risk to organizations includes potential unauthorized access to sensitive configurations and the ability to manipulate the router's functionality. Given the nature of the vulnerability, an attacker may exploit it with low complexity and without requiring authentication. This means that organizations must prioritize patching immediately to safeguard their networks from potential attacks.

The vulnerability was published on December 14, 2016, and remains relevant today, especially since it is included in the CISA Known Exploited Vulnerabilities catalog. Organizations should assess their environments to determine if they are using any of the affected NETGEAR router models and take necessary actions to apply the latest firmware updates.

In light of the potential implications of this vulnerability, it is essential for organizations to remain vigilant and proactive in their security measures, including regular firmware updates and monitoring for any unusual network activity.

Vulnerability Details

The vulnerability allows attackers to execute arbitrary commands due to improper input validation within the affected NETGEAR routers' CGI scripts. The CVSS score of 8.8 indicates a high severity level, highlighting the critical nature of the flaw. The affected products include various firmware versions for models such as R6250, R6400, R7000, and more. This vulnerability is classified under CWE-352, which pertains to improper validation of input.

Technical Analysis

The root cause of CVE-2016-6277 is a failure to adequately sanitize user inputs passed to the command line interface via the CGI scripts of the affected routers. This flaw allows an attacker to inject shell commands through crafted requests, which the router executes, potentially leading to full control over the device.

The attack vector is network-based, requiring the attacker to send specially crafted requests to the device. The complexity of the attack is low, as it does not require extensive technical skills beyond crafting the appropriate HTTP request. No authentication is needed, making this vulnerability particularly dangerous.

User interaction is necessary, as the victim must access a maliciously crafted URL. The impact on confidentiality, integrity, and availability is rated as high, indicating that successful exploitation can lead to serious consequences, including data exfiltration and service disruption.

Risk & Impact Analysis

The real-world deployment risk associated with this vulnerability is significant. As many organizations utilize NETGEAR routers in their networking infrastructure, the potential for widespread exploitation exists. This vulnerability exemplifies the challenges that come with networked devices, particularly those that are remotely accessible.

The blast radius of a successful attack could extend beyond a single device, potentially allowing attackers to pivot to other systems within the network. Organizations must assess their exposure and implement necessary security measures. Given the high CVSS score and inclusion in the KEV catalog, organizations should address this vulnerability in priority patch cycles.

The urgency for remediation is critical, particularly given the potential for exploitation in the wild. Organizations should immediately evaluate their NETGEAR devices and apply necessary patches to mitigate risks.

Exploitation Status

Affected Versions

The following NETGEAR router firmware versions are affected by CVE-2016-6277: R6250 before 1.0.4.6.Beta, R6400 before 1.0.1.18.Beta, R6700 before 1.0.1.14.Beta, R6900, R7000 before 1.0.7.6.Beta, R7100LG before 1.0.0.28.Beta, R7300DST before 1.0.0.46.Beta, R7900 before 1.0.1.8.Beta, R8000 before 1.0.3.26.Beta, D6220, D6400, and D7000.

Mitigation & Remediation

NETGEAR has released patches addressing this vulnerability. Organizations should apply updates per vendor instructions to ensure devices are secured against exploitation. If patches are unavailable, consider implementing network segmentation to restrict access to vulnerable devices and monitor for unusual activity.

For further assistance, organizations may benefit from engaging in penetration testing services to evaluate their security posture.

Detection Guidance

Organizations should monitor logs for unusual command execution patterns and anomalous web requests targeting router management interfaces. Additionally, establishing alerts for suspicious activities can aid in early detection of potential exploitation attempts.

AppSecure Threat Intelligence Insight

CVE-2016-6277 highlights a critical risk associated with networked devices that utilize CGI scripts without proper input validation. This vulnerability serves as a reminder of the importance of secure coding practices and regular updates for IoT devices. Security teams should prioritize vulnerability management to address such issues proactively.

For organizations with NETGEAR routers, the urgency to remediate this vulnerability cannot be overstated. The potential for exploitation in the wild necessitates immediate action, and organizations should familiarize themselves with the latest security advisories and best practices.

For further reading on effective vulnerability management, organizations can refer to the vulnerability management program design guide.

In summary, CVE-2016-6277 underscores the critical need for organizations to maintain vigilant security practices, ensuring that all networked devices are updated and monitored for any signs of compromise.