Heap overflow in kernel driver due to missing size validation
FG-IR-26-156
Summary
CVSSv3 Score:
5.1
An Unverified Ownership Vulnerability [CWE-283] in FortiClient Windows fortimon3 driver may allow an authenticated attacker to terminate arbitrary processes via an exposed minifilter communication port.
Revised on 2026-09-08 00:00:00
Products covered
FortiClient
Remediation
Separate remediation guidance was not included in the collected bulletin.
CVEs in this advisory 1
Update history
What changed in later vendor updates
SecurityAlert records field-level changes from the point we begin following a bulletin. Earlier vendor changes may not have a field-by-field record.
- The vendor changed the advisory summary.
- CVSS changed from 4.7 to 5.1.
- Added CVEs: CVE-2026-84386.
Updates
- Published by Fortinet
The publication date reported by the vendor.
- Added to SecurityAlert
We collected the advisory from the official source.
- Confirmed at the source
Our collector saw this advisory during a later source check.