How severe is CVE-2025-64155?

CVE-2025-64155 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-64155 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 43% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-64155?

CVE-2025-64155 primarily affects Fortinet Fortisiem. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-64155?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-64155 have an EU (EUVD) identifier?

Yes. CVE-2025-64155 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2076.

When was CVE-2025-64155 published?

CVE-2025-64155 was published on 2026-01-13 and last updated on 2026-06-17.

CVE-2025-64155

CVE-2025-64155 is a critical-severity vulnerability in Fortinet Fortisiem with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 43% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-78.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 43% (99th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-2076
Weakness: CWE-78
Affected product: Fortinet Fortisiem
Published: 2026-01-13
Last modified: 2026-06-17

Description

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 6.7.0 through 6.7.10 may allow an attacker to execute unauthorized code or commands via crafted TCP requests.

Frequently asked questions

What is 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 6.7.0 through 6.7.10 may allow an attacker to execute unauthorized code or commands via crafted TCP requests.
How severe is CVE-2025-64155?: CVE-2025-64155 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-64155 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 43% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-64155?: CVE-2025-64155 primarily affects Fortinet Fortisiem. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-64155?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-64155 have an EU (EUVD) identifier?: Yes. CVE-2025-64155 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2076.
When was CVE-2025-64155 published?: CVE-2025-64155 was published on 2026-01-13 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:fortinet:fortisiem:*:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisiem:7.4.0:*:*:*:*:*:*:*

More vulnerabilities in Fortinet Fortisiem

CVE-2024-23109 — Critical (CVSS 10.0): An improper neutralization of special elements used in an os command ('os command injection') vulnerability in Fortinet…
CVE-2024-23108 — Critical (CVSS 10.0): An improper neutralization of special elements used in an os command ('os command injection') vulnerability in Fortinet…
CVE-2023-34992 — Critical (CVSS 10.0): A improper neutralization of special elements used in an os command ('os command injection') vulnerability in Fortinet…
CVE-2023-40714 — Critical (CVSS 9.9): A relative path traversal in Fortinet FortiSIEM versions 7.0.0, 6.7.0 through 6.7.2, 6.6.0 through 6.6.3, 6.5.1, 6.5.0…
CVE-2025-25256 — Critical (CVSS 9.8): An improper neutralization of special elements used in an OS command ('OS Command Injection') vulnerability [CWE-78] in…
CVE-2023-36553 — Critical (CVSS 9.8): A improper neutralization of special elements used in an os command ('os command injection') in Fortinet FortiSIEM…

All CVEs affecting Fortinet Fortisiem →

Other CWE-78 (OS Command Injection) vulnerabilities

CVE-2026-56004 — Critical (CVSS 10.0): A shellcode injection in the mercurial handler of the obs tar_scm source service before version 0.12.4 could be used by…
CVE-2026-56415 — Critical (CVSS 10.0): Storage Concentrator (SC & SCVM) contains a command injection vulnerability within the debug.pl script that is…
CVE-2026-56413 — Critical (CVSS 10.0): Storage Concentrator (SC & SCVM) contains a command injection vulnerability in the ms_service.pl service, which listens…
CVE-2026-49869 — Critical (CVSS 10.0): Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.45 and 1.3.21, AuthenticationFilter in…
CVE-2026-49261 — Critical (CVSS 10.0): MariaDB server is a community developed fork of MySQL server. Versions 10.6.1 through 10.6.26, 10.11.1 through…
CVE-2026-10520 — Critical (CVSS 10.0): An OS Command Injection vulnerability in Ivanti Sentry before the R10.5.2, R10.6.2 and R10.7.1 versions allows a…

Browse all CWE-78 (OS Command Injection) vulnerabilities →