{"cve":"CVE-2021-20826","nvd":{"published":"2021-12-24T07:15:06.510","modified":"2026-06-17T03:34:30.083","status":"Modified","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_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L","score":7.6},"cwes":["CWE-522"],"references":["https://jvn.jp/en/vu/JVNVU92279973/index.html","https://www.idec.com/home/lp/pdf/2021-12-24-PLC.pdf","https://jvn.jp/en/vu/JVNVU92279973/index.html","https://www.idec.com/home/lp/pdf/2021-12-24-PLC.pdf"],"products":["idec:data_file_manager","idec:microsmart_fc6a_firmware","idec:microsmart_plus_fc6a_firmware","idec:windedit","idec:windldr"],"source":"nvd","synced_at":"2026-10-19T21:26:33.761856376+00:00"},"epss":{"cve":"CVE-2021-20826","score":0.00403,"percentile":0.34526,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}