EUVD-2023-35165

Comprehensive Technical Analysis of EUVD-2023-35165

1. Vulnerability Assessment and Severity Evaluation

The vulnerability described in EUVD-2023-35165 pertains to an operating system command injection flaw in the Sangfor Next-Gen Application Firewall version NGAF8.0.17. This vulnerability allows a remote and unauthenticated attacker to execute arbitrary commands by exploiting the mishandling of shell meta-characters in the "un" parameter of the /LogInOut.php 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 base score of 9.8 indicates a critical vulnerability. The CVSS vector breakdown shows that the attack vector is network-based (AV:N), the attack complexity is low (AC:L), no privileges are required (PR:N), no user interaction is needed (UI:N), the scope is unchanged (S:U), and the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H).

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Remote Command Execution: An attacker can send a crafted HTTP POST request to the /LogInOut.php endpoint with malicious shell meta-characters in the "un" parameter.
• Unauthenticated Access: The vulnerability does not require authentication, making it easier for attackers to exploit.

Exploitation Methods:

• Crafted HTTP Requests: Attackers can use tools like curl or custom scripts to send specially crafted HTTP POST requests.
• Automated Scripts: Exploitation can be automated using scripts that target the vulnerable endpoint, making it possible to launch large-scale attacks.

3. Affected Systems and Software Versions

Affected Systems:

• Sangfor Next-Gen Application Firewall

Affected Software Versions:

• Version NGAF8.0.17

4. Recommended Mitigation Strategies

Immediate Actions:

• Patching: Apply the latest security patches provided by Sangfor.
• Network Segmentation: Isolate the affected firewall from critical networks to limit potential damage.
• Monitoring: Increase monitoring of network traffic to detect and respond to suspicious activities.

Long-Term Strategies:

• Regular Updates: Ensure that all security devices are regularly updated with the latest patches.
• Input Validation: Implement robust input validation mechanisms to prevent command injection vulnerabilities.
• Security Audits: Conduct regular security audits and vulnerability assessments.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations using the Sangfor Next-Gen Application Firewall, particularly those in Europe. Given the critical nature of firewalls in network security, successful exploitation could lead to:

• Data Breaches: Unauthorized access to sensitive data.
• Service Disruption: Compromise of network availability and integrity.
• Compliance Issues: Potential violations of data protection regulations such as GDPR.

6. Technical Details for Security Professionals

Vulnerability Details:

• Endpoint: /LogInOut.php
• Parameter: "un"
• Exploit Type: Command Injection
• Shell Meta-Characters: Characters such as ;, &, |, >, <, and $ can be used to inject commands.

Example Exploit:

curl -X POST -d "un=admin; whoami" http://target-firewall/LogInOut.php

Detection:

• Log Analysis: Monitor logs for unusual command execution patterns.
• Intrusion Detection Systems (IDS): Deploy IDS rules to detect and alert on suspicious HTTP POST requests targeting the /LogInOut.php endpoint.

Mitigation:

• Web Application Firewall (WAF): Implement a WAF to filter out malicious input.
• Code Review: Conduct a thorough code review to identify and fix similar vulnerabilities in other endpoints.

References:

• WatchTowr Labs Analysis
• VulnCheck Advisory
• Amazon AWS Marketplace

Aliases:

• CVE-2023-30805
• GSD-2023-30805

Assigner:

• VulnCheck

EPSS Score:

• 84 (indicating a high likelihood of exploitation)

ENISA IDs:

• Product: Net-Gen Application Firewall, Version 8.0.17
• Vendor: Sangfor

By addressing this vulnerability promptly and comprehensively, organizations can significantly reduce the risk of unauthorized command execution and maintain the integrity of their network security infrastructure.