CVE-2021-22659

8.6 HIGH
Published: March 25, 2021 Modified: June 03, 2026
View on NVD

Description

Rockwell Automation MicroLogix 1400 Version 21.6 and below may allow a remote unauthenticated attacker to send a specially crafted Modbus packet allowing the attacker to retrieve or modify random values in the register. If successfully exploited, this may lead to a buffer overflow resulting in a denial-of-service condition. The FAULT LED will flash RED and communications may be lost. Recovery from denial-of-service condition requires the fault to be cleared by the user.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-033-01
Source: ics-cert@hq.dhs.gov
Third Party Advisory US Government Resource
https://rockwellautomation.custhelp.com/app/answers/answer_view/a_id/1129877/loc/en_US#__highlight
Source: af854a3a-2127-422b-91ae-364da2661108
Permissions Required Vendor Advisory
https://us-cert.cisa.gov/ics/advisories/icsa-21-033-01
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory US Government Resource

4 reference(s) from NVD

Quick Stats

CVSS v3 Score
8.6 / 10.0
EPSS (Exploit Probability)
1.7%
75th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

rockwellautomation