EUVD-2023-28271

Comprehensive Technical Analysis of EUVD-2023-28271

1. Vulnerability Assessment and Severity Evaluation

The vulnerability EUVD-2023-28271, also known as CVE-2023-24212, pertains to a stack overflow in the Tenda AX3 router firmware version V16.03.12.11. The stack overflow occurs via the timeType function within the /goform/SetSysTimeCfg endpoint. The CVSS (Common Vulnerability Scoring System) base score of 9.8 indicates a critical severity level. The CVSS vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H breaks down as follows:

• Attack Vector (AV:N): Network, meaning the vulnerability is exploitable over the network.
• Attack Complexity (AC:L): Low, indicating that the attack is relatively straightforward to execute.
• Privileges Required (PR:N): None, meaning no special privileges are needed to exploit the vulnerability.
• User Interaction (UI:N): None, indicating that no user interaction is required.
• Scope (S:U): Unchanged, meaning the vulnerability does not affect other security scopes.
• Confidentiality (C:H): High impact on confidentiality.
• Integrity (I:H): High impact on integrity.
• Availability (A:H): High impact on availability.

This high severity score underscores the critical nature of the vulnerability, which can lead to significant security breaches if exploited.

2. Potential Attack Vectors and Exploitation Methods

The stack overflow vulnerability can be exploited through the following methods:

• Remote Code Execution (RCE): An attacker can send a specially crafted request to the /goform/SetSysTimeCfg endpoint, causing a stack overflow. This can lead to arbitrary code execution on the router, allowing the attacker to take control of the device.
• Denial of Service (DoS): The stack overflow can also cause the router to crash, resulting in a denial of service. This can disrupt network connectivity for all users connected to the router.
• Data Exfiltration: By exploiting the vulnerability, an attacker can potentially access sensitive information stored on the router, such as configuration settings and network credentials.

3. Affected Systems and Software Versions

The vulnerability specifically affects Tenda AX3 routers running firmware version V16.03.12.11. It is crucial to note that other versions of the firmware may also be affected, but this has not been confirmed. Users and administrators should verify the firmware version of their Tenda AX3 routers to determine if they are at risk.

4. Recommended Mitigation Strategies

To mitigate the risk associated with this vulnerability, the following steps are recommended:

• Firmware Update: Immediately update the Tenda AX3 router to the latest firmware version provided by the manufacturer. Ensure that the update process is conducted securely to prevent any further vulnerabilities.
• Network Segmentation: Implement network segmentation to isolate the router from critical systems and limit the potential impact of an exploit.
• Firewall Rules: Configure firewall rules to restrict access to the router's management interface, allowing only trusted IP addresses.
• Intrusion Detection Systems (IDS): Deploy IDS to monitor network traffic for suspicious activities that may indicate an attempt to exploit the vulnerability.
• Regular Audits: Conduct regular security audits and vulnerability assessments to identify and address potential security weaknesses.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to the European cybersecurity landscape, particularly for organizations and individuals relying on Tenda AX3 routers for network connectivity. The potential for remote code execution and data exfiltration can lead to severe security breaches, including unauthorized access to sensitive information, network disruptions, and potential financial losses. The widespread use of routers in both residential and commercial settings amplifies the impact, making it a critical concern for cybersecurity professionals and policymakers.

6. Technical Details for Security Professionals

For security professionals, the following technical details are essential:

• Vulnerable Function: The timeType function within the /goform/SetSysTimeCfg endpoint is the point of vulnerability.
• Exploitation: The stack overflow can be triggered by sending a maliciously crafted HTTP request to the endpoint. The request should contain a payload designed to overflow the stack buffer.
• Detection: Monitor network traffic for unusual patterns, such as repeated requests to the /goform/SetSysTimeCfg endpoint with large payloads. Use IDS/IPS systems to detect and block such attempts.
• Patch Analysis: Review the patch provided by Tenda to understand the changes made to mitigate the vulnerability. Ensure that the patch addresses the root cause of the stack overflow.
• Incident Response: Develop an incident response plan that includes steps for isolating affected routers, containing the breach, and restoring normal operations.

Conclusion

The vulnerability EUVD-2023-28271 in Tenda AX3 routers is a critical concern for cybersecurity professionals. The potential for remote code execution, denial of service, and data exfiltration underscores the need for immediate mitigation strategies. Updating the firmware, implementing network segmentation, configuring firewall rules, deploying IDS, and conducting regular audits are essential steps to protect against this vulnerability. The impact on the European cybersecurity landscape highlights the importance of proactive security measures and continuous monitoring.

References

• GitHub Repository 1
• GitHub Repository 2