CVE-2025-66601 Cross-site scripting in FAST/TOOLS

Medium 6.3 Published 9 Feb 2026 Updated 9 Feb 2026

Attackers can execute malicious scripts via content sniffing due to missing MIME type specifications in Yokogawa FAST/TOOLS.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2025-66601?

CVE-2025-66601 is a medium-severity cross-site scripting vulnerability in Yokogawa Electric Corporation FAST/TOOLS, published on 9 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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

This product does not specify MIME types. When an attacker performs a content sniffing attack, malicious scripts could be executed.

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

Weakness: CWE-358

Which versions are affected by CVE-2025-66601?

It affects 1 product.

Products include Yokogawa Fast\/Tools.

How do I fix CVE-2025-66601?

No fix has been published for CVE-2025-66601 yet. Limit exposure of the affected software until one is available.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2025-66601 being exploited?

There is no known exploitation of CVE-2025-66601 in the wild and no public exploit code.

Sources

Also known as GHSA-pc5p-g2cg-mr66.