What is CVE-2025-64155?

CVE-2025-64155 is a critical-severity vulnerability in Fortinet Fortisiem, classified under OS Command Injection. CVSS score: 9.4/10. Published 2026-01-13.

How severe is CVE-2025-64155?

Critical severity. CVSS v3 base score is 9.4 out of 10.

Is CVE-2025-64155 known to be exploited?

4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

RCE in Fortinet Fortisiem

CVE-2025-64155

An improper neutralization of special elements used in an os command ('os command injection') vulnerability in Fortinet FortiSIEM 7.4.0, FortiSIEM 7.3.0 through 7.3.4, FortiSIEM 7.1.0 through 7.1.8, FortiSIEM 7.0.0 through 7.0.4, FortiSIEM…

Vulnerability class: Command Injection (OS Command Injection)

EPSS: 0.001 (23.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.4 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C.

Affected products

Fortinet Fortisiem — versions 7.4.0, 7.3.0, 7.2.6

Weakness classification (CWE)

CWE-78 — OS Command Injection

Public proof-of-concept exploits

References

https://fortiguard.fortinet.com/psirt/FG-IR-25-772

Frequently asked questions

What is CVE-2025-64155?: CVE-2025-64155 is a critical-severity vulnerability in Fortinet Fortisiem, classified under OS Command Injection. CVSS score: 9.4/10. Published 2026-01-13.
How severe is CVE-2025-64155?: Critical severity. CVSS v3 base score is 9.4 out of 10.
Is CVE-2025-64155 known to be exploited?: 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.