Fortinet Fixes Critical FortiSIEM Flaw Allowing Unauthenticated Remote Code Execution

The Hacker News

January 14, 2026 at 11:53 AM

Overview

Fortinet has addressed a severe vulnerability in its FortiSIEM product that could allow attackers to execute arbitrary code without authentication. This flaw, known as CVE-2025-64155, has a CVSS score of 9.4, highlighting its potential impact on affected systems. The vulnerability arises from improper handling of special elements in OS commands, which could be exploited by malicious actors. Organizations using FortiSIEM should prioritize applying the latest updates to protect their systems. The existence of such vulnerabilities emphasizes the need for ongoing vigilance in maintaining security protocols and software updates.

Key Takeaways

Affected Systems: FortiSIEM
Action Required: Users should update to the latest version of FortiSIEM as released by Fortinet to mitigate this vulnerability.
Timeline: Newly disclosed

Original Article Summary

Fortinet has released updates to fix a critical security flaw impacting FortiSIEM that could allow an unauthenticated attacker to achieve code execution on susceptible instances. The operating system (OS) injection vulnerability, tracked as CVE-2025-64155, is rated 9.4 out of 10.0 on the CVSS scoring system. "An improper neutralization of special elements used in an OS command ('OS command

Impact

FortiSIEM

Exploitation Status

The exploitation status is currently unknown. Monitor vendor advisories and security bulletins for updates.

Timeline

Newly disclosed

Remediation

Users should update to the latest version of FortiSIEM as released by Fortinet to mitigate this vulnerability.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Fortinet, Vulnerability, and 1 more.

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