CVE-2021-32986 CRITICAL

CVE-2021-32986: Automation Direct CLICK PLC CPU Modules Authentication Bypass Using an Alternate Path or Channel

Vendor Automation Direct
Product CLICK PLC CPU Modules: C0-1x CPUs
Weakness CWE-288
Published April 4, 2022
Last update April 16, 2025
View on NVD All CVEs

CVSS base score

9.8/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

What the vulnerability does

01Description

After Automation Direct CLICK PLC CPU Modules: C0-1x CPUs with firmware prior to v3.00 is unlocked by an authorized user, the unlocked state does not timeout. If the programming software is interrupted, the PLC remains unlocked. All subsequent programming connections are allowed without authorization. The PLC is only relocked by a power cycle, or when the programming software disconnects correctly.

Key dates

02Disclosure timeline

April 4, 2022 CVE published
April 16, 2025 Record updated

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