EUVD-2024-38355

Comprehensive Technical Analysis of EUVD-2024-38355

1. Vulnerability Assessment and Severity Evaluation

The vulnerability EUVD-2024-38355, also known as CVE-2024-39761, is a critical OS command injection vulnerability affecting the Wavlink AC3000 M33A8.V5030.210505 device. The vulnerability resides in the login.cgi set_sys_init() functionality, specifically within the restart_week_value POST parameter. This vulnerability allows an attacker to execute arbitrary code by sending a specially crafted HTTP request.

Severity Evaluation:

• Base Score: 10.0 (Critical)
• Base Score Version: CVSS 3.1
• Base Score Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

The CVSS score of 10.0 indicates the highest level of severity. The vulnerability can be exploited over the network (AV:N), requires low complexity (AC:L), does not require 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). The scope change (S:C) indicates that the vulnerability affects components beyond the initial security scope.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Unauthenticated HTTP Request: An attacker can send a specially crafted HTTP request to the vulnerable endpoint without needing authentication.
• Command Injection: The attacker can inject malicious commands through the restart_week_value POST parameter, leading to arbitrary code execution.

Exploitation Methods:

• Crafting Malicious HTTP Requests: The attacker can use tools like curl or Burp Suite to craft and send HTTP requests with malicious payloads.
• Automated Scripts: Attackers can write scripts to automate the exploitation process, making it easier to target multiple devices.

3. Affected Systems and Software Versions

Affected Systems:

• Device: Wavlink AC3000
• Firmware Version: M33A8.V5030.210505

Vendor Information:

• Vendor: WAVLINK
• ENISA ID Vendor: f29f4512-a110-36af-9eef-31d74e39674a

4. Recommended Mitigation Strategies

Immediate Mitigation:

• Network Segmentation: Isolate affected devices from critical networks to limit the potential impact of an attack.
• 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 provided by WAVLINK as soon as they are available.
• Patch Management: Implement a robust patch management process to ensure timely updates of all devices.
• Security Audits: Conduct regular security audits and vulnerability assessments to identify and mitigate potential vulnerabilities.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to European organizations and individuals using the affected Wavlink AC3000 devices. Given the critical nature of the vulnerability, it can be exploited to gain unauthorized access, steal sensitive information, and disrupt network operations. The widespread use of such devices in homes and businesses amplifies the potential impact, making it crucial for European cybersecurity authorities to address this issue promptly.

6. Technical Details for Security Professionals

Vulnerability Details:

• Vulnerable Function: set_sys_init() in login.cgi
• Vulnerable Parameter: restart_week_value
• Exploitation: The vulnerability can be triggered by injecting OS commands into the restart_week_value parameter via an HTTP POST request.

Example Exploit:

curl -X POST -d "restart_week_value=;<malicious_command>" http://<target_ip>/login.cgi

Detection:

• Log Analysis: Monitor logs for unusual HTTP requests targeting the login.cgi endpoint.
• Intrusion Detection Systems (IDS): Implement IDS rules to detect and alert on suspicious traffic patterns.

Response:

• Incident Response Plan: Develop and implement an incident response plan to quickly address any detected exploitation attempts.
• Communication: Inform stakeholders and users about the vulnerability and provide guidance on mitigation steps.

References:

• Talos Intelligence Report: TALOS-2024-2018

By addressing this vulnerability promptly and effectively, organizations can significantly reduce the risk of exploitation and protect their networks from potential attacks.