Is CVE-2025-66603 in the CISA KEV catalog?

No. CVE-2025-66603 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2025-66603?

CVE-2025-66603 has a CVSS v3 base score of 9.8 (CRITICAL).

What is the EPSS score for CVE-2025-66603?

CVE-2025-66603 has an EPSS score of 0.26% (17th percentile), estimating the probability of exploitation in the next 30 days.

CVE & CISA-KEV Catalog

CVE-2025-66603

CRITICAL

9.8

CVSS v3

NVD

Description

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

CWE-358

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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

Exploit Intelligence

0.26%probability of exploitation in 30 days

17thpercentile

Low risk: more likely to be exploited than 17% of all known CVEs.

References

https://web-material3.yokogawa.com/1/39206/files/YSAR-26-0001-E.pdf

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-03-05.