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CVE-2025-66602NVD status: Analyzed

FAST/TOOLS: Reliance on IP Address for Authentication

CVE-2025-66602 is a critical-severity reliance on IP address for authentication vulnerability in FAST/TOOLS from Yokogawa Electric, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected FAST/TOOLS versions: R9.01 through R10.04. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.36% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of FAST/TOOLS you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on web-material3.yokogawa.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Yokogawa ElectricFAST/TOOLSR9.01 through R10.04Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.06.9MediumCNA
CVSS 3.19.8CriticalNVD

Official description

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

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Reliance on IP Address for Authentication

The product uses an IP address for authentication.

How developers prevent this class of flaw

  • Use other means of identity verification that cannot be simply spoofed. Possibilities include a username/password or certificate. While IP address verification can be a useful part of an authentication scheme, but it should not be the single factor required for authentication.

More Reliance on IP Address for Authentication vulnerabilities (CWE-291)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in FAST/TOOLS

All FAST/TOOLS vulnerabilities

Recent Reliance on IP Address for Authentication vulnerabilities

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