CVE-2023-40718 : Security Advisory and Response

This article provides detailed information about CVE-2023-40718, a vulnerability in Fortinet IPS Engine versions 7.321, 7.166, and 6.158 that allows attackers to evade IPS features via crafted TCP packets.

Understanding CVE-2023-40718

CVE-2023-40718 is a vulnerability in Fortinet IPS Engine that affects versions 7.321, 7.166, and 6.158. The vulnerability allows attackers to bypass IPS features using specially crafted TCP packets.

What is CVE-2023-40718?

The vulnerability arises from an interpretation conflict in the affected versions of Fortinet IPS Engine. Attackers can exploit this vulnerability to evade detection and protection mechanisms provided by the IPS Engine.

The Impact of CVE-2023-40718

The impact of CVE-2023-40718 includes a reduction in the effectiveness of the IPS Engine in detecting and preventing malicious activities. Attackers can potentially bypass intrusion prevention systems using this vulnerability.

Technical Details of CVE-2023-40718

CVE-2023-40718 is classified under CWE-436: Improper access control. The CVSS score for this vulnerability is 6.7, indicating a medium severity level with high integrity impact.

Vulnerability Description

The vulnerability allows attackers to evade IPS features by exploiting an interpretation conflict in Fortinet IPS Engine versions 7.321, 7.166, and 6.158 via crafted TCP packets.

Affected Systems and Versions

Fortinet IPS Engine versions 7.321, 7.166, and 6.158 are affected by this vulnerability, potentially impacting devices using these specific versions.

Exploitation Mechanism

Attackers can exploit this vulnerability by sending specially crafted TCP packets to the affected Fortinet IPS Engine, enabling them to evade intrusion prevention systems.

Mitigation and Prevention

To mitigate the risks associated with CVE-2023-40718, immediate actions should be taken to secure systems and prevent exploitation.

Immediate Steps to Take

Users are advised to update their Fortinet IPS Engine to version 6.0159 or later to address this vulnerability. It is recommended to apply available patches and updates to fortify the security of the systems.

Long-Term Security Practices

In the long term, organizations should maintain regular updates of their IPS Engine versions and keep security mechanisms up to date to prevent future vulnerabilities.

Patching and Updates

Fortinet has released fixed versions for the affected IPS Engine, including 6.0159, 7.0166, 7.0313, and subsequent versions. Users are encouraged to update their IPS Engine to the latest secure versions for enhanced protection.