Fortinet SSL VPN RCE Vulnerability - Patches Released

Threat Advisory
Written By Lee Vaniderstine

Fortinet has identified a critical vulnerability affecting several of its products that utilize SSL-VPN functionalities. This vulnerability, known as CVE-2023-27997, poses a significant threat by allowing unauthenticated remote code execution on vulnerable devices. Enterprotect, a leading cybersecurity company, urges organizations to take immediate action to mitigate this risk. In this advisory, we will delve into the technical details of the threat, discuss its importance, outline the potential exposure and risks, and provide expert recommendations to safeguard your network.

What is the Threat?

CVE-2023-27997 is a heap-based buffer overflow vulnerability that affects FortiOS and FortiProxy. This security flaw grants unauthenticated users the ability to remotely crash devices and potentially execute arbitrary code or commands. SSL-VPN functionalities, which are critical for secure remote access to organizational networks, are impacted by this vulnerability. While there is currently no evidence of exploitation in the wild, it is crucial to address this vulnerability promptly to ensure the safety of your systems.

Why is it Noteworthy?

Fortinet, a renowned provider of security solutions, is widely adopted across various sectors, including remote offices, small businesses, and expansive campuses. The significance of this vulnerability lies in its pre-authentication accessibility on every SSL-VPN appliance. The SSL-VPN functionality plays a crucial role in enabling remote users to securely connect to organizational resources. Consequently, the exposure of this service can have severe consequences for the affected system and the entire network.

What is the Exposure or Risk?

Exploiting CVE-2023-27997 grants unauthenticated users the ability to remotely crash devices and execute arbitrary code. This compromise can lead to a loss of integrity, availability, and confidentiality of the affected system, placing the entire network at risk. Fortinet has promptly released patches to address this vulnerability. To ensure the security of your organization, it is recommended to upgrade to the following versions:

  • FortiOS-6K7K version 7.0.12 or above

  • FortiOS-6K7K version 6.4.13 or above

  • FortiOS-6K7K version 6.2.15 or above

  • FortiOS-6K7K version 6.0.17 or above

  • FortiProxy version 7.2.4 or above

  • FortiProxy version 7.0.10 or above

  • FortiOS version 7.4.0 or above

  • FortiOS version 7.2.5 or above

  • FortiOS version 7.0.12 or above

  • FortiOS version 6.4.13 or above

  • FortiOS version 6.2.14 or above

  • FortiOS version 6.0.17 or above

What are the Recommendations?

Enterprotect recommends the following actions to minimize the impact of the Fortinet SSL VPN RCE vulnerability:

  1. Disable SSL-VPN as a Work-Around: Temporarily disabling SSL-VPN functionality can reduce the exposure to potential attacks. However, this should be considered a temporary measure until the appropriate patches are applied.

  2. Apply the Latest Patches: Fortinet has released patches specifically designed to address this vulnerability. It is crucial to apply the latest patches promptly to ensure your systems are protected. Keep your Fortinet products up to date by installing the recommended versions mentioned earlier.

  3. Practice Good Cyber Hygiene: Maintain strong cybersecurity practices within your organization. Implement robust access controls, employ multi-factor authentication (MFA), and regularly update and patch all software and firmware to mitigate the risk of potential vulnerabilities.

  4. Stay Informed: Stay up to date with the latest advisories from Fortinet. Regularly monitor their security bulletins and promptly apply any recommended patches or updates.

Enterprotect is committed to providing comprehensive cybersecurity solutions, and we strongly encourage organizations to take immediate action to address this vulnerability. By following these recommendations, you can significantly reduce the risk of falling victim to the Fortinet SSL VPN RCE vulnerability.

References

For more in-depth information about the recommendations, please visit the following links:

Lee Vaniderstine
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