Fortinet PSIRT AdvisoriesFG-IR-26-147

Missed certificate verification in AD Connector communication with FortiClient EMS

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

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6.7CVSS out of 10Medium severity

Scope

What the vendor says is affected

FortiClient

Timeline

When this advisory changed

Jul 14, 2026 at 7:00 AM UTC
Published by Fortinet
The publication date reported by the vendor.
Aug 20, 2026 at 2:50 AM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Sep 13, 2026 at 5:10 AM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Source

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Vendor: Fortinet
Advisory ID: FG-IR-26-147
Last source check: Sep 13, 2026 at 5:10 AM UTC

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