EUVD-2023-37826

Comprehensive Technical Analysis of EUVD-2023-37826

1. Vulnerability Assessment and Severity Evaluation

The vulnerability identified in EUVD-2023-37826 pertains to a stack overflow in the Tenda AC8V4.0-V16.03.34.06 firmware, specifically within the sub_4a79ec function via the time parameter. 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:

• AV:N (Attack Vector: Network): The vulnerability is exploitable over the network.
• AC:L (Attack Complexity: Low): The attack requires minimal skill or resources.
• PR:N (Privileges Required: None): No privileges are required to exploit the vulnerability.
• UI:N (User Interaction: None): No user interaction is required.
• S:U (Scope: Unchanged): The vulnerability does not change the security scope.
• C:H (Confidentiality: High): The vulnerability has a high impact on confidentiality.
• I:H (Integrity: High): The vulnerability has a high impact on integrity.
• A:H (Availability: High): The vulnerability has a 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 specially crafted network packets to the affected device, causing a stack overflow in the sub_4a79ec function. This can lead to arbitrary code execution with elevated privileges.
• Denial of Service (DoS): By exploiting the stack overflow, an attacker can crash the device, rendering it unavailable for legitimate users.
• Data Exfiltration: The vulnerability can be used to exfiltrate sensitive information from the device, including configuration data and user credentials.

3. Affected Systems and Software Versions

The vulnerability specifically affects Tenda AC8V4.0 devices running firmware version V16.03.34.06. It is crucial to identify and update all devices running this firmware version to mitigate the risk.

4. Recommended Mitigation Strategies

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

• Firmware Update: Immediately update the firmware to a version that addresses this vulnerability. Regularly check for and apply firmware updates from the vendor.
• Network Segmentation: Isolate affected devices on a separate network segment to limit the potential impact of an exploit.
• Firewall Rules: Implement strict firewall rules to restrict access to the affected devices, allowing only necessary traffic.
• Intrusion Detection Systems (IDS): Deploy IDS to monitor network traffic for signs of exploitation attempts.
• Regular Audits: Conduct regular security audits and vulnerability assessments to identify and address potential security issues.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to the European cybersecurity landscape, particularly for organizations and individuals using Tenda AC8V4.0 devices. The potential for remote code execution and data exfiltration can lead to severe security breaches, including unauthorized access to sensitive information, disruption of services, and potential financial losses. Organizations must prioritize the identification and mitigation of this vulnerability to protect their networks and data.

6. Technical Details for Security Professionals

For security professionals, the following technical details are pertinent:

• Vulnerable Function: The stack overflow occurs in the sub_4a79ec function when processing the time parameter.
• Exploitation: The vulnerability can be triggered by sending a specially crafted network packet that overflows the stack buffer.
• Detection: Monitor network traffic for unusual patterns or anomalies that may indicate an exploitation attempt. Use tools like Wireshark to analyze network packets.
• Mitigation: Ensure that all Tenda AC8V4.0 devices are updated to the latest firmware version. Implement network security measures such as firewalls, IDS, and regular security audits.

Conclusion

EUVD-2023-37826 represents a critical vulnerability in Tenda AC8V4.0 devices that requires immediate attention. Organizations must prioritize firmware updates and implement robust network security measures to mitigate the risk. The potential impact on the European cybersecurity landscape underscores the importance of proactive vulnerability management and regular security assessments.

References

• GitHub Repository
• GitHub Tree

For further technical details and updates, refer to the provided GitHub links and the official Tenda website for firmware updates.