CVE-2026-59836
CVSSv3 Score: 6.7 An Improper Certificate Validation vulnerability [CWE-295] in FortiClient EMS may allow a remote unauthenticated attacker to impersonate an AD Connector via a valid API Key. Revised on 2026-07-14 00:00:00
CSIRTS triage
- What
- A remote unauthenticated attacker may impersonate an AD Connector via a valid API Key.
- Who is affected
- Users of FortiClient EMS with AD Connector integration.
- Urgency
- Remediation is critical to prevent impersonation attacks.
- Action
- Ensure proper certificate validation is implemented.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Low exploitation risk0.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all EPSS-scored CVEs.
Advisory coverage (5)
- unknownNCSC-2026-0243 [1.00] [M/H] Vulnerability fixed in Fortinet FortiClient EMSncsc-nl · 2026-07-17
- medium[NEW] [medium] Fortinet FortiClient EMS: Vulnerability allows bypassing security measurescert-bund · 2026-07-15
- unknownMultiple vulnerabilities in Fortinet products (July 15, 2026)cert-fr-avis · 2026-07-15
- highCVE-2026-59836: A improper certificate validation vulnerability in Fortinet FortiClientEMS 7.4.3 through 7.4.5…nvd · 2026-07-14
- unknownMissed certificate verification in AD Connector communication with FortiClient EMSfortinet · 2026-07-14
External references
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