# Yokogawa FAST/TOOLS exposes CI Server config data

Published: 2026-06-25 · Severity: medium · Sectors: manufacturing, energy
Canonical: https://vorant.io/reports/929d5167-97f6-54dd-bac0-ac366f15322d/yokogawa-fast-tools-exposes-ci-server-config-data

> A cleartext transmission flaw in Yokogawa FAST/TOOLS R9.01–R10.04 and CI Server R1.01–R1.04 leaks server configuration data that could enable further attacks against critical manufacturing and energy systems.

CISA has published an advisory for CVE-2026-11833, an information disclosure vulnerability in Yokogawa's FAST/TOOLS and Collaborative Information Server (CI Server) affecting critical manufacturing, energy, and food/agriculture sectors worldwide. The web server returns responses containing CI Server setting information in cleartext, which attackers could leverage for reconnaissance and subsequent attacks. Affected versions include FAST/TOOLS R9.01 through R10.04 and CI Server R1.01 through R1.04.

Yokogawa has released remediation guidance, recommending users update FAST/TOOLS to R10.04 and apply patch software R10.04 SP4, and update CI Server to R1.05. The vulnerability stems from cleartext transmission of sensitive information (CWE-319). No active exploitation has been reported to CISA at the time of advisory publication.

CISA emphasizes standard ICS defensive measures: isolate control systems from the internet, place them behind firewalls separate from business networks, and use secure remote access methods like VPNs. Organizations should consult Yokogawa's security advisory YSAR-26-0004 for detailed implementation guidance.

## Mentioned in this report

- Vulnerabilities: CVE-2026-11833

Source reporting: https://www.cisa.gov/news-events/ics-advisories/icsa-26-176-01

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