EUVD-2023-37930

Comprehensive Technical Analysis of EUVD-2023-37930

1. Vulnerability Assessment and Severity Evaluation

The vulnerability EUVD-2023-37930 affects multiple Draytek Vigor devices, including routers, access points, switches, and Myvigor firmware. The core issue is the use of hardcoded encryption keys, which allows attackers to bind any affected device to their own account. This vulnerability is rated with a CVSS Base Score of 9.8, indicating 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 low complexity.
• 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): There is a high impact on confidentiality.
• I:H (Integrity: High): There is a high impact on integrity.
• A:H (Availability: High): There is a high impact on availability.

2. Potential Attack Vectors and Exploitation Methods

Attackers can exploit this vulnerability by:

• Network Scanning: Identifying vulnerable devices on the network.
• Binding Devices: Using the hardcoded encryption keys to bind the devices to their own accounts.
• Creating Licenses: Generating WCF and DrayDDNS licenses and synchronizing them from the website.
• Unauthorized Access: Gaining unauthorized access to the device's configuration and data.

3. Affected Systems and Software Versions

The affected systems and their respective firmware versions are:

• Draytek Vigor Routers: Firmware versions below 3.9.6/4.2.4
• Access Points: Firmware versions below v1.4.0
• Switches: Firmware versions below 2.6.7
• Myvigor: Firmware versions below 2.3.2

4. Recommended Mitigation Strategies

To mitigate this vulnerability, the following steps should be taken:

• Firmware Updates: Immediately update the firmware of all affected devices to the latest versions:
  • Routers: 3.9.6/4.2.4 or later
  • Access Points: v1.4.0 or later
  • Switches: 2.6.7 or later
  • Myvigor: 2.3.2 or later
• Network Segmentation: Implement network segmentation to isolate critical devices.
• Access Control: Enforce strict access control policies to limit unauthorized access.
• Monitoring: Implement continuous monitoring to detect any unusual activity.
• Encryption: Ensure that all communications are encrypted using strong, non-hardcoded keys.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to the European cybersecurity landscape, particularly for organizations and individuals using Draytek Vigor devices. The potential for unauthorized access and manipulation of network devices can lead to data breaches, service disruptions, and other cybersecurity incidents. The widespread use of Draytek devices in both enterprise and consumer environments amplifies the risk.

6. Technical Details for Security Professionals

• Hardcoded Encryption Keys: The use of hardcoded encryption keys is a fundamental flaw that undermines the security of the devices. Attackers can easily extract these keys and use them to bind devices to their own accounts.
• Exploitation Steps:
  1. Identify Vulnerable Devices: Use network scanning tools to identify devices with vulnerable firmware versions.
  2. Extract Encryption Keys: Extract the hardcoded encryption keys from the firmware.
  3. Bind Devices: Use the extracted keys to bind the devices to the attacker's account.
  4. Create Licenses: Generate and synchronize WCF and DrayDDNS licenses.
  5. Gain Unauthorized Access: Access and manipulate the device's configuration and data.
• Detection: Implement intrusion detection systems (IDS) and intrusion prevention systems (IPS) to detect and prevent unauthorized access attempts.
• Response: Develop an incident response plan to quickly address any detected exploitation attempts.

Conclusion

EUVD-2023-37930 is a critical vulnerability affecting multiple Draytek Vigor devices. The use of hardcoded encryption keys allows attackers to bind devices to their own accounts, creating significant risks for confidentiality, integrity, and availability. Immediate firmware updates and robust security measures are essential to mitigate this vulnerability and protect the European cybersecurity landscape.

References

• GitHub Gist
• Aliases: CVE-2023-33778, GSD-2023-33778
• Assigner: Mitre
• EPSS: N/A
• ENISA ID Product: n/a
• ENISA ID Vendor: n/a