Critical Vulnerabilities in Fortinet's FortiMonitorOnSight and Privileged Access Agent Chrome Extension

H-ISAC Vulnerability Bulletins TLP WHITE: Critical Vulnerabilities in Fortinet's FortiMonitorOnSight and Privileged Access Agent Chrome Extension (CVE-2026-84390 & CVE-2026-84388)

Fortinet has issued security updates addressing 10 vulnerabilities across various products. Key flaws include an authentication bypass flaw in the FortiMonitorOnSight web portal that uses forged JSON Web Tokens (CVE-2026-84390) and a proxy flaw in the Fortinet Privileged Access Agent Chrome extension (CVE-2026-84388).

View the detailed report below. 

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