EUVD-2025-6522

Comprehensive Technical Analysis of EUVD-2025-6522

1. Vulnerability Assessment and Severity Evaluation

The vulnerability identified in Tenda AC9 v1.0 V15.03.05.14_multi involves a stack overflow in the mac parameter of the /goform/AdvSetMacMtuWan endpoint. This flaw can be exploited to achieve remote arbitrary code execution. The CVSS (Common Vulnerability Scoring System) base score of 9.8 indicates a critical severity level. The scoring 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): Network (N) - The vulnerability is exploitable over the network.
• Attack Complexity (AC): Low (L) - The attack requires minimal skill or resources.
• Privileges Required (PR): None (N) - No privileges are required to exploit the vulnerability.
• User Interaction (UI): None (N) - No user interaction is required.
• Scope (S): Unchanged (U) - The vulnerability does not change the security scope.
• Confidentiality (C): High (H) - Complete loss of confidentiality.
• Integrity (I): High (H) - Complete loss of integrity.
• Availability (A): High (H) - Complete loss of availability.

Given these factors, the vulnerability is considered highly critical and poses a significant risk to affected systems.

2. Potential Attack Vectors and Exploitation Methods

The primary attack vector is through network access to the vulnerable endpoint. An attacker could send a specially crafted request to the /goform/AdvSetMacMtuWan endpoint with a malicious mac parameter, causing a stack overflow. This overflow can be leveraged to execute arbitrary code on the device, potentially leading to full system compromise.

Potential exploitation methods include:

• Direct Network Attack: An attacker with network access can send malicious HTTP requests to the vulnerable endpoint.
• Man-in-the-Middle (MitM) Attack: An attacker could intercept and modify legitimate requests to include the malicious payload.
• Phishing: Tricking users into visiting a malicious website that sends the crafted request to the vulnerable device.

3. Affected Systems and Software Versions

The vulnerability specifically affects Tenda AC9 v1.0 with firmware version V15.03.05.14_multi. Other versions of the Tenda AC9 or different models may also be affected if they share the same codebase or firmware components. It is crucial to verify the impact on other versions and models through further analysis.

4. Recommended Mitigation Strategies

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

• Firmware Update: Immediately apply any available firmware updates provided by Tenda. If no update is available, contact Tenda support for guidance.
• Network Segmentation: Isolate the affected devices on a separate network segment to limit exposure.
• Access Control: Implement strict access controls to limit network access to the vulnerable endpoint.
• Intrusion Detection/Prevention Systems (IDS/IPS): Deploy IDS/IPS to monitor and block suspicious network traffic targeting the vulnerable endpoint.
• Regular Audits: Conduct regular security audits and vulnerability assessments to identify and address similar issues proactively.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to the European cybersecurity landscape, particularly for organizations and individuals using Tenda AC9 routers. The potential for remote arbitrary code execution can lead to data breaches, unauthorized access, and disruption of services. Given the widespread use of routers in both residential and commercial settings, the impact could be far-reaching, affecting critical infrastructure, businesses, and personal users.

6. Technical Details for Security Professionals

For security professionals, the following technical details are essential:

• Vulnerable Endpoint: /goform/AdvSetMacMtuWan
• Vulnerable Parameter: mac
• Exploitation Method: Stack overflow leading to arbitrary code execution.
• Detection: Monitor network traffic for unusual patterns targeting the vulnerable endpoint. Implement logging and alerting mechanisms to detect and respond to suspicious activities.
• Response: In case of an exploitation attempt, isolate the affected device, capture forensic data, and follow incident response procedures to contain and mitigate the impact.

References:

• NVD Entry
• GitHub Analysis

By addressing this vulnerability promptly and effectively, organizations can significantly reduce the risk of exploitation and maintain the integrity and security of their networks.