OS command injection in FortiSIEM - CVE-2025-64155
Published: January 13, 2026 / Updated: January 16, 2026
Vulnerability identifier: #VU121224
CSH Severity: Critical
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Red
CVE-ID: CVE-2025-64155
CWE-ID: CWE-78
Exploitation vector: Remote access
Exploit availability:
Public exploit is available
Vendor: Fortinet, Inc
Affected software:
FortiSIEM
FortiSIEM
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary shell commands on the target system.
The vulnerability exists due to improper input validation in phMonitor. A remote unauthenticated attacker can send specially crafted packets to port 7900/TCP and execute arbitrary OS commands on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
How to mitigate CVE-2025-64155
Install updates from vendor's website.