CVE-2021-22659: Buffer Overflow

Published Mar 25, 2021
·
Updated

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.

Affected Software

4 affected components
rockwellautomation Micrologix 1400 Firmware<=21.6
rockwellautomation Micrologix 1400
All of the following
rockwellautomation Micrologix 1400 Firmware<=21.6
rockwellautomation Micrologix 1400

Event History

Mar 25, 2021
CVE Published
via MITRE·03:59 PM
Data Sourced
via MITRE·03:59 PM
DescriptionWeakness
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software
Aug 3, 2024
Data Sourced
via ICS·06:54 PM
SeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-22659?

CVE-2021-22659 is a vulnerability in Rockwell Automation MicroLogix 1400 Version 21.6 and below that allows a remote unauthenticated attacker to retrieve or modify random values in the register.

2

What is the severity of CVE-2021-22659?

The severity of CVE-2021-22659 is high with a severity value of 8.6.

3

How can an attacker exploit CVE-2021-22659?

An attacker can exploit CVE-2021-22659 by sending a specially crafted Modbus packet to the vulnerable device.

4

What is the impact of successfully exploiting CVE-2021-22659?

Successfully exploiting CVE-2021-22659 may lead to a buffer overflow, resulting in a denial-of-service condition.

5

How can I fix CVE-2021-22659?

To fix CVE-2021-22659, Rockwell Automation advises upgrading to a version of MicroLogix 1400 firmware that is higher than 21.6.

Contact

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