CVE-2021-22681

Insufficient Protected Credentials in Rockwell Multiple Products. CISA confirmed attackers exploit it and added it to its Known Exploited Vulnerabilities catalog on 5 March 2026.

Product: Rockwell Multiple Products
Added to CISA's catalog: 5 March 2026
Federal fix-by date: 26 March 2026
Ransomware: No known use in ransomware campaigns
Vendor advisories: support.rockwellautomation.com/app/answers/answer_view/a_id/1130301/~/cve-2021-22681%3A-authentication-bypass-vulnerability-found-in-logix-controllers-
Sources: CISA’s catalog, NVD entry

CISA’s description.

Multiple Rockwell products contain an insufficient protected credentials vulnerability. Studio 5000 Logix Designer software may allow a key to be discovered. This key is used to verify Logix controllers are communicating with Rockwell Automation design software. If successfully exploited, this vulnerability could allow an unauthorized application to connect with Logix controllers. To leverage this vulnerability, an unauthorized user would require network access to the controller.

Every flaw CISA confirmed exploited in the last 30 days is on the exploit watch. This is not security advice. Check the vendor’s advisory before acting. From CISA’s catalog of 4 November 2026.