What is the CVSS score of CVE-2025-66602?

CVE-2025-66602 has a CVSS 3.1 base score of 9.8 (Critical). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.1%.

Which versions of Fast Tools are affected by CVE-2025-66602?

A critical vulnerability in Yokogawa FAST/TOOLS web server allows unauthorized access via IP-based authentication bypass, potentially exposing industrial control systems to remote attackers.

How to fix or mitigate CVE-2025-66602?

Within 24 hours: Identify and inventory all FAST/TOOLS installations; restrict network access to the web server using firewall rules limiting connectivity to authorized IPs only; disable remote access if not operationally required. Within 7 days: Implement web application firewall (WAF) rules to block suspicious access patterns; conduct security assessment of affected systems; establish enhanced monitoring and logging. Within 30 days: Coordinate with Yokogawa for patch availability; plan and execute patching in controlled maintenance windows; validate remediation across all instances.

Fast Tools CVE-2025-66602

CRITICAL

Reliance on IP Address for Authentication (CWE-291)

2026-02-09 7168b535-132a-4efe-a076-338f829b2eb9

Information Disclosure Fast Tools

9.8

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

9.8 CRITICAL

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 21:54 vuln.today

CVE Published

Feb 09, 2026 - 04:15 nvd

CRITICAL 9.8

DescriptionCVE.org

A vulnerability has been found in FAST/TOOLS provided by Yokogawa Electric Corporation.

The web server accepts access by IP address. When a worm that randomly searches for IP addresses intrudes into the network, it could potentially be attacked by the worm.

The affected products and versions are as follows: FAST/TOOLS (Packages: RVSVRN, UNSVRN, HMIWEB, FTEES, HMIMOB) R9.01 to R10.04

AnalysisAI

Yokogawa FAST/TOOLS SCADA has a vulnerability in its web server component enabling unauthorized access to the industrial control monitoring system.

Technical ContextAI

Yokogawa FAST/TOOLS has a CWE-291 reliance on IP address for authentication vulnerability in its web server component, allowing attackers to bypass access controls.