CVE-2021-20826
HIGH
Published Dec 24, 20214y ago · Modified Jun 17, 20261w ago
7.6 CVSS 3.1
Published Dec 24, 2021 4y ago
Last Modified Jun 17, 2026 1w ago
Description
Unprotected transport of credentials 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 the communication between the PLC and the software. As a result, the complete access privileges to the PLC Web server may be obtained, and manipulation of the PLC output and/or suspension of the PLC may be conducted.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L Attack Vector Adjacent
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity Low
Availability Low
Threat Intelligence
No active exploitation signals — not in CISA KEV and no EPSS score yet.
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-522
Affected Products 7
References 2
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.