CVE-2026-21644 was reserved as a potential vulnerability identifier by Fortinet but subsequently rejected, indicating that the reported issue was either invalid, a duplicate, or otherwise not recognized as a security vulnerability. The lack of any technical details, affected product versions, or exploit data confirms that this CVE does not correspond to a real or exploitable security flaw. The absence of a CVSS score and patch information further supports that this is not an actionable threat. The REJECTED state means that security teams should not allocate resources to address this CVE, as it does not represent a genuine risk.

Since CVE-2026-21644 is marked as REJECTED and lacks any technical or exploit information, it poses no impact to organizations, including those in Europe. There is no risk to confidentiality, integrity, or availability from this entry. European organizations do not need to consider this CVE in their threat models or vulnerability management processes.

No mitigation actions are necessary for CVE-2026-21644 due to its REJECTED status and absence of any confirmed vulnerability. Organizations should continue to follow standard security best practices and monitor for valid CVEs affecting their environments. It is recommended to verify CVE statuses through trusted sources to avoid unnecessary remediation efforts.