
CVE-2023-37936 is a critical security vulnerability identified in Fortinet FortiSwitch devices. This vulnerability is particularly severe due to its potential to allow unauthorized code execution, leading to a complete compromise of affected network devices. Here is an in-depth examination of the details, impacts, and mitigation strategies for this vulnerability.
Vulnerability Details
- CVE-2023-37936:
- Discovered in: Fortinet FortiSwitch versions 7.4.0, 7.2.0 through 7.2.5, 7.0.0 through 7.0.7, 6.4.0 through 6.4.13, 6.2.0 through 6.2.7, and 6.0.0 through 6.0.7.
- CVSS Score: 9.6 (Critical)
- Description: The vulnerability arises due to the use of a hard-coded cryptographic key within FortiSwitch devices. Attackers with knowledge of this key can craft and send malicious requests to execute unauthorized code or commands on the vulnerable devices. This flaw can lead to a total compromise of the network infrastructure.
Exploitation Method
Attackers can exploit CVE-2023-37936 through the following steps:
- Identifying Vulnerable Devices: Attackers scan networks to identify FortiSwitch devices running affected versions.
- Crafting Malicious Requests: Using the hard-coded cryptographic key, attackers craft malicious requests that can bypass authentication mechanisms.
- Executing Unauthorized Code: The crafted requests allow attackers to execute arbitrary code on the affected devices, giving them full control.
Impact
The impact of CVE-2023-37936 is severe, with significant potential consequences including:
- Unauthorized Code Execution: Attackers can execute arbitrary code on vulnerable FortiSwitch devices, leading to unauthorized access and control.
- Network Compromise: The vulnerability allows attackers to gain full control over the network devices, posing a significant threat to the overall security of the network infrastructure.
- Data Exfiltration: Attackers can use compromised devices to exfiltrate sensitive data, leading to data breaches.
- Service Disruption: Unauthorized code execution can result in service disruption, impacting the availability and reliability of network services.
Mitigation
To protect against CVE-2023-37936, it is crucial to apply the patches released by Fortinet and follow recommended security practices:
- Patch: Fortinet has released patches for all supported versions of FortiSwitch to address this vulnerability. Users are strongly urged to update their devices to the following versions or later:
- FortiSwitch 7.4: Update to version 7.4.1 or later
- FortiSwitch 7.2: Update to version 7.2.6 or later
- FortiSwitch 7.0: Update to version 7.0.8 or later
- FortiSwitch 6.4: Update to version 6.4.14 or later
- FortiSwitch 6.2: Update to version 6.2.8 or later
- Note: FortiSwitch 6.0 has reached its end-of-life (EOL), and users are advised to migrate to a supported version with the necessary fixes.
- Restrict Access: Limit access to network devices to trusted IP addresses only. Implement access control lists (ACLs) and firewall rules to restrict network access to the FortiSwitch management interfaces.
- Monitor for Unusual Activity: Implement robust monitoring solutions to detect any suspicious or unusual activity on network devices. Set up alerts for unauthorized access attempts and unusual traffic patterns.
- Review and Harden Configurations: Regularly review and update device configurations to follow security best practices. Disable unnecessary services and features to minimize the attack surface.
Conclusion
CVE-2023-37936 underscores the critical importance of maintaining up-to-date security measures and promptly applying security patches. By following Fortinet’s recommendations and implementing the necessary updates, users can protect their network infrastructure from potential exploitation and ensure a secure and stable environment.


