What is CVE-2025-66597?

CVE-2025-66597 is a high-severity vulnerability in Yokogawa Fast\/tools, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 7.5/10. Published 2026-02-09.

How severe is CVE-2025-66597?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in Yokogawa Fast\/tools

CVE-2025-66597

A vulnerability has been found in FAST/TOOLS provided by Yokogawa Electric Corporation. This product supports weak cryptographic algorithms, potentially allowing an attacker to decrypt communications with the web server. The affected products and versions are as follows: FAST/TOOLS (Packages: RVSVRN, UNSVRN, HMIWEB, FTEES, HMIMOB) R9.01 to R10.04

Vulnerability class: POODLE (CVE-2014-3566)

Published 2026-02-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.002 (6.4th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 6.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

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

Weakness classification (CWE)

CWE-327 — Use of a Broken or Risky Cryptographic Algorithm

References

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

Frequently asked questions

What is CVE-2025-66597?: CVE-2025-66597 is a high-severity vulnerability in Yokogawa Fast\/tools, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 7.5/10. Published 2026-02-09.
How severe is CVE-2025-66597?: High severity. CVSS v3 base score is 7.5 out of 10.