Fortinet hit by another exploited cybersecurity flaw

A critical SQL injection vulnerability, identified as CVE-2026-21643, has been exploited in Fortinet's management server, allowing unauthenticated attackers to execute arbitrary code on unpatched systems via crafted HTTP requests. This flaw specifically targets the FortiClient Endpoint Management Server, a widely-used cybersecurity tool. The vulnerability has a low complexity, making it easily exploitable by threat actors. As recently as the current discussions, the CVE was being actively abused, highlighting the urgency of the situation. The exploitation status of CVE-2026-21643 is a key factor in determining whether immediate patching or monitoring is required¹. This vulnerability poses a significant risk to organizations relying on Fortinet's products, particularly those using the FortiClient Endpoint Management Server. So what matters to practitioners is that they must prioritize patching or closely monitoring their systems to prevent potential breaches.