CVE-2024-26008 is a denial of service vulnerability identified in Fortinet's FortiProxy, FortiOS, FortiPAM, and FortiSwitchManager products. The root cause is an improper check or handling of exceptional conditions (CWE-703) within the fgfm daemon, a core component responsible for managing Fortinet device communications. This flaw allows an unauthenticated attacker to send specially crafted SSL-encrypted TCP requests that cause the fgfm daemon to repeatedly reset its connections. This repeated reset can lead to service disruption, effectively causing a denial of service condition. The vulnerability affects FortiOS versions 7.4.0 through 7.4.3 and versions prior to 7.2.7, FortiProxy versions 7.4.0 through 7.4.3 and before 7.2.9, FortiPAM versions before 1.2.0, and FortiSwitchManager versions 7.2.0 through 7.2.3 and 7.0.0 through 7.0.3. The CVSS v3.1 base score is 5.0 (medium severity) with vector AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L, indicating network attack vector, low complexity, no privileges or user interaction required, and impact limited to availability. No known exploits have been reported in the wild yet, but the vulnerability could be leveraged to disrupt network security services, potentially impacting enterprise operations. The vulnerability is significant because it targets core Fortinet infrastructure components widely used in enterprise and service provider environments for secure network traffic management and device communication.

For European organizations, the primary impact of CVE-2024-26008 is the potential disruption of network security and management services provided by Fortinet products. Denial of service on FortiProxy or FortiOS devices can interrupt secure web traffic filtering, VPN services, and firewall operations, leading to degraded network performance or outages. This can affect business continuity, especially for organizations relying heavily on Fortinet for perimeter defense and secure remote access. Critical infrastructure sectors such as finance, healthcare, telecommunications, and government agencies could experience operational disruptions. Additionally, repeated fgfm connection resets may complicate device management and monitoring, increasing the risk of delayed incident response. Although no data confidentiality or integrity impact is indicated, availability degradation can have cascading effects on dependent services and compliance with regulatory requirements like GDPR. The medium severity rating suggests moderate risk but warrants prompt attention due to the widespread use of affected Fortinet versions in Europe.

1. Monitor Fortinet’s official advisories and apply patches or firmware updates as soon as they become available for the affected Fortinet products and versions. 2. Implement network-level protections such as rate limiting and anomaly detection on SSL-encrypted TCP traffic targeting Fortinet management interfaces to detect and block suspicious fgfm connection reset attempts. 3. Restrict access to Fortinet management interfaces (fgfm daemon) to trusted internal networks or VPNs, minimizing exposure to unauthenticated external attackers. 4. Employ robust network segmentation to isolate critical Fortinet devices from general user traffic and potential attack sources. 5. Enable detailed logging and monitoring of fgfm connections to identify unusual reset patterns indicative of exploitation attempts. 6. Conduct regular vulnerability assessments and penetration testing focused on Fortinet infrastructure to verify the effectiveness of mitigations. 7. Prepare incident response plans specifically addressing potential denial of service scenarios affecting Fortinet devices to ensure rapid recovery and continuity.