EUVD-2025-203927

Comprehensive Technical Analysis of EUVD-2025-203927

1. Vulnerability Assessment and Severity Evaluation

The vulnerability EUVD-2025-203927, also known as CVE-2025-67073, is a buffer overflow issue in the fromAdvSetMacMtuWan function of the httpd binary in Tenda AC10V4.0 V16.03.10.20. This vulnerability allows remote attackers to cause a denial of service (DoS) and potentially execute arbitrary code by sending a specially crafted POST request to the /goform/AdvSetMacMtuWan endpoint.

Severity Evaluation:

• CVSS Base Score: 9.8
• CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

The high CVSS score of 9.8 indicates a critical vulnerability. The vector breakdown shows that the attack can be executed over the network (AV:N), requires low complexity (AC:L), does not need any privileges (PR:N) or user interaction (UI:N), and has a high impact on confidentiality, integrity, and availability (C:H/I:H/A:H).

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Remote Exploitation: Attackers can exploit this vulnerability remotely by sending a malicious POST request to the affected endpoint.
• Network-Based Attacks: Given the nature of the vulnerability, it can be exploited over the network, making it accessible to a wide range of attackers.

Exploitation Methods:

• Crafted Payload: The attacker crafts a POST request with a specially designed payload in the serviceName field.
• Buffer Overflow: The payload is designed to overflow the buffer in the fromAdvSetMacMtuWan function, leading to a DoS condition or code execution.

3. Affected Systems and Software Versions

Affected Systems:

• Device: Tenda AC10V4.0
• Firmware Version: V16.03.10.20

Software Component:

• Binary: httpd
• Function: fromAdvSetMacMtuWan

4. Recommended Mitigation Strategies

Immediate Mitigation:

• Network Segmentation: Isolate affected devices from critical networks to limit the potential impact.
• Firewall Rules: Implement strict firewall rules to block unauthorized access to the /goform/AdvSetMacMtuWan endpoint.
• Intrusion Detection Systems (IDS): Deploy IDS to monitor and alert on suspicious traffic patterns targeting the vulnerable endpoint.

Long-Term Mitigation:

• Firmware Update: Apply the latest firmware updates from Tenda as soon as they are available.
• Code Review: Conduct a thorough code review of the httpd binary to identify and fix similar vulnerabilities.
• Security Training: Educate network administrators and users about the importance of regular updates and security best practices.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to European organizations and individuals using the Tenda AC10V4.0 device. Given the widespread use of such devices in both home and enterprise environments, the potential for large-scale disruption and data breaches is high. The European Union's focus on cybersecurity, as evidenced by initiatives like the NIS Directive and GDPR, underscores the need for prompt and effective mitigation strategies.

6. Technical Details for Security Professionals

Vulnerability Details:

• Function: fromAdvSetMacMtuWan
• Endpoint: /goform/AdvSetMacMtuWan
• Payload Field: serviceName

Exploitation Steps:

1. Identify Target: Scan for devices running Tenda AC10V4.0 V16.03.10.20.
2. Craft Payload: Develop a POST request with a payload designed to overflow the buffer in the serviceName field.
3. Send Request: Use tools like curl or custom scripts to send the malicious request to the target device.

Detection and Monitoring:

• Log Analysis: Monitor HTTP logs for unusual POST requests to the /goform/AdvSetMacMtuWan endpoint.
• Behavioral Analysis: Use behavioral analysis tools to detect anomalous network behavior indicative of exploitation attempts.

Patching and Updates:

• Vendor Communication: Engage with Tenda for the latest firmware updates and patches.
• Automated Updates: Implement automated update mechanisms to ensure devices are promptly patched.

Conclusion: EUVD-2025-203927 represents a critical vulnerability that requires immediate attention from cybersecurity professionals. By understanding the technical details and implementing robust mitigation strategies, organizations can protect themselves from potential exploitation and maintain the integrity of their networks.