CVE-2020-6988: rockwellautomation micrologix_1400_b_firmware Use of Client-Side Authentication

Vulnerability summary

CVE-2020-6988 is a high (CVSS 7.5) Use of Client-Side Authentication vulnerability in rockwellautomation micrologix_1400_b_firmware. EPSS estimates a 4.02% chance of exploitation in the next 30 days, higher than 90.4% of scored vulnerabilities.

Timeline

1. 16-03-2020
   PublishedVulnerability first disclosed.
2. 03-06-2026
   Last modifiedVulnerability information updated.

Description

Rockwell Automation MicroLogix 1400 Controllers Series B v21.001 and prior, Series A, all versions, MicroLogix 1100 Controller, all versions, RSLogix 500 Software v12.001 and prior, A remote, unauthenticated attacker can send a request from the RSLogix 500 software to the victim’s MicroLogix controller. The controller will then respond to the client with used password values to authenticate the user on the client-side. This method of authentication may allow an attacker to bypass authentication altogether, disclose sensitive information, or leak credentials.

• CWE-603Use of Client-Side AuthenticationA client/server product performs authentication within client code but not in server code, allowing server-side authentication to be bypassed via a modified client that omits the authentication check.
• CWE-287Improper AuthenticationWhen an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.