What’s Vulnerable › Vulnerabilities

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

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.1% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2022-04-04 · updated 2026-06-17
• Weakness: CWE-288

Description

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.

Affected products

• AutomationDirect C0-10Are-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-10Dd1E-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-10Dd2E-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-10Dre-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-11Are-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-11Dd1E-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-11Dd2E-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-11Dre-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Are-1-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Are-2-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Are-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Dd1E-1-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Dd1E-2-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Dd1E-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Dd2E-1-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Dd2E-2-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Dd2E-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Dre-1-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Dre-2-D Firmware: before 3.00 — fixed in 3.00
• AutomationDirect C0-12Dre-D Firmware: before 3.00 — fixed in 3.00

How to fix

Upgrade to a fixed version: AutomationDirect C0-10Are-D Firmware 3.00; AutomationDirect C0-10Dd1E-D Firmware 3.00; AutomationDirect C0-10Dd2E-D Firmware 3.00; AutomationDirect C0-10Dre-D Firmware 3.00; AutomationDirect C0-11Are-D Firmware 3.00; AutomationDirect C0-11Dd1E-D Firmware 3.00; AutomationDirect C0-11Dd2E-D Firmware 3.00; AutomationDirect C0-11Dre-D Firmware 3.00; AutomationDirect C0-12Are-1-D Firmware 3.00; AutomationDirect C0-12Are-2-D Firmware 3.00; AutomationDirect C0-12Are-D Firmware 3.00; AutomationDirect C0-12Dd1E-1-D Firmware 3.00. Check the vendor advisory for mitigations.

References

• https://www.cisa.gov/uscert/ics/advisories/icsa-21-166-02
• https://www.cisa.gov/uscert/ics/advisories/icsa-21-166-02

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