What is CVE-2025-66603?

CVE-2025-66603 is a critical-severity vulnerability in Yokogawa Fast\/tools, classified under CWE-358. CVSS score: 9.8/10. Published 2026-02-09.

How severe is CVE-2025-66603?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Vulnerability in Yokogawa Fast\/tools

CVE-2025-66603

A vulnerability has been found in FAST/TOOLS provided by Yokogawa Electric Corporation. The web server accepts the OPTIONS method. An attacker could potentially use this information to carry out other attacks. The affected products and versions are as follows: FAST/TOOLS (Packages: RVSVRN, UNSVRN, HMIWEB, FTEES, HMIMOB) R9.01 to R10.04

EPSS: 0.003 (17.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Yokogawa Fast\/tools
Yokogawa Electric Corporation Fast/tools — versions R9.01

Weakness classification (CWE)

CWE-358

References

7168b535-132a-4efe-a076-338f829b2eb9 (Vendor Advisory)

Frequently asked questions

What is CVE-2025-66603?: CVE-2025-66603 is a critical-severity vulnerability in Yokogawa Fast\/tools, classified under CWE-358. CVSS score: 9.8/10. Published 2026-02-09.
How severe is CVE-2025-66603?: Critical severity. CVSS v3 base score is 9.8 out of 10.