CVE-2021-22681: listed in the CISA KEV catalog
CVE-2021-22681 · CVSS 9.8 CRITICAL · EPSS 61% · KEV 2026-03-05
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.
Is CVE-2021-22681 exploited?
- Listed in the CISA KEV catalog on 2026-03-05.
- Federal remediation due 2026-03-26.
- Past that date by 142 days.
- EPSS puts exploitation in the next 30 days at 61%.
- Public exploit code: none found in monitored sources.
Which products and versions are affected?
No affected package list recorded here yet.
Is there a patch?
No patch identifier recorded here yet.
What PlainSec published about CVE-2021-22681
Primary sources
What this record does not say
- No affected package data.
- No patch identifier.
KEV and EPSS are re-checked daily. Record last updated 2026-08-11.