Vulnerability identifier: #VU51000

Vulnerability risk: High

CVSSv3.1: 9.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H/E:U/RL:U/RC:C]

CVE-ID: CVE-2021-22681

CWE-ID: CWE-522

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
RSLogix 5000
Server applications / Other server solutions
Studio 5000 Logix Designer
Client/Desktop applications / Other client software

Vendor: Rockwell Automation

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to the affected product uses a key to verify Logix controllers are communicating with the affected Rockwell Automation products. A remote attacker can bypass this verification mechanism and authenticate with Logix controllers.

This vulnerability affects the following Rockwell Logix Controllers:

• CompactLogix 1768
• CompactLogix 1769
• CompactLogix 5370
• CompactLogix 5380
• CompactLogix 5480
• ControlLogix 5550
• ControlLogix 5560
• ControlLogix 5570
• ControlLogix 5580
• DriveLogix 5560
• DriveLogix 5730
• DriveLogix 1794-L34
• Compact GuardLogix 5370
• Compact GuardLogix 5380
• GuardLogix 5570
• GuardLogix 5580
• SoftLogix 5800

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

RSLogix 5000: 16 - 20

Studio 5000 Logix Designer: 21

---

External links
http://ics-cert.us-cert.gov/advisories/icsa-21-056-03
http://ics-cert.kaspersky.com/advisories/klcert-advisories/2021/03/02/klcert-17-029-authentication-bypass-in-rockwell-automation-logix-controllers
http://rockwellautomation.custhelp.com/app/answers/answer_view/a_id/1130301

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.