EUVD-2023-59107

Comprehensive Technical Analysis of EUVD-2023-59107

1. Vulnerability Assessment and Severity Evaluation

The vulnerability EUVD-2023-59107, classified as critical, affects the Totolink A7100RU router, specifically version 7.4cu.2313_B20191024. The issue resides in the HTTP POST Request Handler, particularly in the function main of the file /cgi-bin/cstecgi.cgi?action=login. The manipulation of the argument flag with the input ie8 leads to a buffer overflow, which can be exploited remotely.

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 base score indicates a severe vulnerability due to the following factors:

• Attack Vector (AV:N): The vulnerability can be exploited over the network.
• Attack Complexity (AC:L): The attack requires low complexity.
• Privileges Required (PR:N): No privileges are required to exploit the vulnerability.
• User Interaction (UI:N): No user interaction is required.
• Scope (S:U): The vulnerability does not change the security scope.
• Confidentiality (C:H), Integrity (I:H), Availability (A:H): All three security properties are highly impacted.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Remote Exploitation: An attacker can send a specially crafted HTTP POST request to the vulnerable endpoint /cgi-bin/cstecgi.cgi?action=login with the argument flag set to ie8.
• Buffer Overflow: The manipulation of the flag argument causes a buffer overflow, which can lead to arbitrary code execution or a denial of service (DoS).

Exploitation Methods:

• Code Execution: An attacker can inject malicious code into the buffer, leading to remote code execution (RCE).
• DoS Attack: The buffer overflow can cause the device to crash, resulting in a DoS condition.

3. Affected Systems and Software Versions

Affected Systems:

• Totolink A7100RU router

Affected Software Versions:

• Firmware version 7.4cu.2313_B20191024

4. Recommended Mitigation Strategies

Immediate Mitigation:

• Network Segmentation: Isolate the affected devices from critical networks.
• Firewall Rules: Implement strict firewall rules to block unauthorized access to the vulnerable endpoint.
• Monitoring: Increase monitoring of network traffic to detect and respond to suspicious activities.

Long-Term Mitigation:

• Firmware Update: Apply the latest firmware updates from the vendor once available.
• Patch Management: Implement a robust patch management process to ensure timely updates.
• Security Audits: Conduct regular security audits and vulnerability assessments.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to European cybersecurity, particularly for organizations and individuals using the affected Totolink A7100RU routers. The potential for remote exploitation and the high impact on confidentiality, integrity, and availability make it a critical concern. Organizations should prioritize mitigation efforts to prevent potential breaches and ensure the security of their networks.

6. Technical Details for Security Professionals

Vulnerability Details:

• Vulnerable Component: HTTP POST Request Handler
• Vulnerable Function: main in /cgi-bin/cstecgi.cgi?action=login
• Trigger: Manipulation of the flag argument with the input ie8
• Impact: Buffer overflow leading to RCE or DoS

References:

• VulDB Entry
• CTI Entry
• GitHub Repository

Aliases:

• CVE-2023-6906
• GSD-2023-6906

Assigner:

• VulDB

ENISA IDs:

• Product:
  • ID: 26c4b76f-92de-3697-a477-bad7cc0abb12
  • Product Name: A7100RU
  • Product Version: 7.4cu.2313_B20191024
  • ID: ff5e26f1-0880-33df-85ae-fccf0494b165
  • Product Name: A7100RU
• Vendor:
  • ID: fe7bb576-b501-30af-b1dc-c6e1ae6b14cc
  • Vendor Name: Totolink

Conclusion: The vulnerability EUVD-2023-59107 in the Totolink A7100RU router is critical and requires immediate attention. Organizations should implement both immediate and long-term mitigation strategies to protect their networks from potential exploitation. Regular updates and security audits are essential to maintain a robust cybersecurity posture.