The CVE-2026-21645 entry was reserved by Fortinet but subsequently rejected, indicating that the vulnerability either does not exist, was a duplicate, or was otherwise invalidated. No technical details, affected product versions, or exploit information have been published. The lack of a CVSS score and absence of patches or mitigations further support that this is not an active or confirmed vulnerability. Without concrete data on the nature of the vulnerability, its impact, or exploitability, it is not possible to provide a detailed technical explanation or risk assessment. The rejection status suggests that this CVE should not be considered a security threat at this time.

Given the rejection status and absence of technical details or known exploits, there is no identifiable impact on confidentiality, integrity, or availability. European organizations are not currently at risk from this entry. No disruption or compromise attributable to this CVE has been reported or is expected based on the available information.

No specific mitigation measures are necessary due to the rejection of this CVE and lack of evidence of a vulnerability. Organizations should continue to follow standard cybersecurity best practices and maintain up-to-date security patches for all Fortinet products and other infrastructure. Monitoring official vulnerability databases and vendor advisories for any future developments related to this or similar CVEs is recommended.