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CVE-2021-22681

Rockwell Automation Studio 5000 Logix Designer Versions 21 and later, and RSLogix 5000 Versions 16 through 20 use a key to verify Logix controllers...

Basic Information

CVE State: PUBLISHED
Reserved Date: January 05, 2021
Published Date: March 03, 2021
Last Updated: March 05, 2026
Vendor: n/a
Product: Rockwell Automation Studio 5000 Logix Designer, RSLogix 5000, Logix Controllers
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.
Tags

CVSS Scores

CVSS v3.1

9.8 - CRITICAL

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

CVSS v2.0

7.5

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P

SSVC Information

Exploitation: active
Automatable: Yes
Technical Impact: total

Exploit Status

Exploited in the Wild: Yes (2026-06-01 11:38:00 UTC) Source

References

https://us-cert.cisa.gov/ics/advisories/icsa-21-056-03

Known Exploited Vulnerability Information

Source	Added Date
CVE	2026-06-01 11:38:00 UTC

Timeline

CVE ID Reserved

January 05, 2021
CVE Published to Public

March 03, 2021
Added to KEVIntel

June 01, 2026