CVE-2021-22681

CriticalActively exploited (CISA KEV)

Description

Rockwell Automation Studio 5000 Logix Designer Versions 21 and later, and RSLogix 5000 Versions 16 through 20 use a key to verify Logix controllers are communicating with Rockwell Automation CompactLogix 1768, 1769, 5370, 5380, 5480: ControlLogix 5550, 5560, 5570, 5580; DriveLogix 5560, 5730, 1794-L34; Compact GuardLogix 5370, 5380; GuardLogix 5570, 5580; SoftLogix 5800. Rockwell Automation Studio 5000 Logix Designer Versions 21 and later and RSLogix 5000: Versions 16 through 20 are vulnerable because an unauthenticated attacker could bypass this verification mechanism and authenticate with Rockwell Automation CompactLogix 1768, 1769, 5370, 5380, 5480: ControlLogix 5550, 5560, 5570, 5580; DriveLogix 5560, 5730, 1794-L34; Compact GuardLogix 5370, 5380; GuardLogix 5570, 5580; SoftLogix 5800.

SeverityCritical
CVSS9.8
Exploit probability—
ProductRockwell Multiple Products
PublishedMar 3, 2021
First seenMar 3, 2021
Added to KEVMar 5, 2026
Weakness typeCWE-522CWE-522

How to fix

CISA required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

CISA due date: Mar 26, 2026

Affected products

ProductAffected versionsFixed in
rockwellautomation rslogix_500016 ≤ v ≤ 20—
rockwellautomation factorytalk_services_platform2.10 ≤ v—
rockwellautomation studio_5000_logix_designer21.0 ≤ v—

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

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