CVE-2021-20591: High severity mitsubishi electric r00cpu firmware vulnerability

Published Jun 11, 2021
·
Updated

Uncontrolled Resource Consumption vulnerability in Mitsubishi Electric MELSEC iQ-R series CPU modules (R00/01/02CPU all versions, R04/08/16/32/120(EN)CPU all versions, R08/16/32/120SFCPU all versions, R08/16/32/120PCPU all versions, R08/16/32/120PSFCPU all versions) allows a remote unauthenticated attacker to prevent legitimate clients from connecting to the MELSOFT transmission port (TCP/IP) by not closing a connection properly, which may lead to a denial of service (DoS) condition.

Affected Software

40 affected components
Mitsubishielectric R00cpu Firmware
Mitsubishielectric R00cpu
Mitsubishielectric R01cpu Firmware
Mitsubishielectric R01cpu
Mitsubishielectric R02cpu Firmware
Mitsubishielectric R02cpu
Mitsubishielectric R04cpu Firmware
Mitsubishielectric R04cpu
Mitsubishielectric R08cpu Firmware
Mitsubishielectric R08cpu
Mitsubishielectric R16cpu Firmware
Mitsubishielectric R16cpu
Mitsubishielectric R32cpu Firmware
Mitsubishielectric R32cpu
Mitsubishielectric R120cpu Firmware
Mitsubishielectric R120cpu
Mitsubishielectric R08sfcpu Firmware
Mitsubishielectric R08sfcpu
Mitsubishielectric R16sfcpu Firmware
Mitsubishielectric R16sfcpu
Mitsubishielectric R32sfcpu Firmware
Mitsubishielectric R32sfcpu
Mitsubishielectric R120sfcpu Firmware
Mitsubishielectric R120sfcpu
Mitsubishielectric R08pcpu Firmware
Mitsubishielectric R08pcpu
Mitsubishielectric R16pcpu Firmware
Mitsubishielectric R16pcpu
Mitsubishielectric R32pcpu Firmware
Mitsubishielectric R32pcpu
Mitsubishielectric R120pcpu Firmware
Mitsubishielectric R120pcpu
Mitsubishielectric R08psfcpu Firmware
Mitsubishielectric R08psfcpu
Mitsubishielectric R16psfcpu Firmware
Mitsubishielectric R16psfcpu
Mitsubishielectric R32psfcpu Firmware
Mitsubishielectric R32psfcpu
Mitsubishielectric R120psfcpu Firmware
Mitsubishielectric R120psfcpu

Event History

Jun 11, 2021
CVE Published
via MITRE·03:52 PM
Data Sourced
via MITRE·03:52 PM
DescriptionWeakness
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Frequently Asked Questions

1

What is CVE-2021-20591?

CVE-2021-20591 is a vulnerability in Mitsubishi Electric MELSEC iQ-R series CPU modules that allows a remote unauthenticated attacker to cause uncontrolled resource consumption.

2

What is the severity of CVE-2021-20591?

The severity of CVE-2021-20591 is high with a CVSS score of 7.5.

3

Which software versions are affected by CVE-2021-20591?

The vulnerability affects all versions of Mitsubishi Electric MELSEC iQ-R series CPU modules, including R00/01/02CPU, R04/08/16/32/120(EN)CPU, R08/16/32/120SFCPU, R08/16/32/120PCPU, and R08/16/32/120PSFCPU.

4

How can an attacker exploit CVE-2021-20591?

An attacker can exploit CVE-2021-20591 remotely and without authentication to cause uncontrolled resource consumption.

5

Are there any fixes or patches available for CVE-2021-20591?

Yes, Mitsubishi Electric has released a patch to address the vulnerability. Please refer to the official advisory for further instructions.

Contact

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