# 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 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 Ro

- **CVSS:** 9.8 (CRITICAL)
- **EPSS:** 15.4%
- **CISA KEV:** yes
- **CWE:** CWE-522

Canonical: https://intel.threadlinqs.com/cve/CVE-2021-22681
Full threat coverage + IOCs via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp