CVE intelligence and bounded remediation

CVE-2021-20827 — Idec Microsmart Fc6A Firmware security vulnerability

High CVSS 7.5

Plaintext storage of a password vulnerability in IDEC PLCs (FC6A Series MICROSmart All-in-One CPU module v2.32 and earlier, FC6A Series MICROSmart Plus CPU module v1.91 and earlier, WindLDR v8.19.1 and earlier, WindEDIT Lite v1.3.1 and earlier, and Data File Manager v2.12.1 and earlier) allows an attacker to obtain the PLC Web server user credentials from file servers, backup repositories, or ZLD files saved in SD cards. As a result, the attacker may access the PLC Web server and hijack the PLC, and manipulation of the PLC output and/or suspension of the PLC may be conducted.

Severity
High
CVSS
7.5 (3.1)
Published
2021-12-24
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-312

Affected products

  • idec / microsmart_fc6a_firmware
  • idec / microsmart_plus_fc6a_firmware
  • idec / data_file_manager
  • idec / windedit
  • idec / windldr

Matched remediation archetype

General vulnerability remediation

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Confirm the affected component, deployment paths, reachable interfaces, and enabled features from inventories and configuration, without probing production destructively.
  • Compare the advisory's affected conditions with the repository lockfiles, build manifests, artifacts, and runtime inventory.
  • Identify data sensitivity, trust boundaries, and privilege level for every confirmed affected deployment.

Remediate safely

  • Apply a vendor-supported fix or remove the affected component or feature; record the selected change and its source in the repository.
  • Update direct and transitive dependency locks, generated artifacts, deployment manifests, and asset inventories together.
  • Add a regression test for the documented unsafe condition using inert inputs and preserve rollback instructions.

Authoritative sources

Complete CVE record and remediation plan

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