CVE-2020-5668: High severity Mitsubishielectric R00cpu Firmware vulnerability

Published Nov 20, 2020
·
Updated

Uncontrolled resource consumption vulnerability in MELSEC iQ-R Series modules (R00/01/02CPU firmware version '19' and earlier, R04/08/16/32/120 (EN) CPU firmware version '51' and earlier, R08/16/32/120SFCPU firmware version '22' and earlier, R08/16/32/120PCPU firmware version '25' and earlier, R08/16/32/120PSFCPU firmware version '06' and earlier, RJ71EN71 firmware version '47' and earlier, RJ71GF11-T2 firmware version '47' and earlier, RJ72GF15-T2 firmware version '07' and earlier, RJ71GP21-SX firmware version '47' and earlier, RJ71GP21S-SX firmware version '47' and earlier, and RJ71GN11-T2 firmware version '11' and earlier) allows a remote unauthenticated attacker to cause an error in a CPU unit and cause a denial-of-service (DoS) condition in execution of the program and its communication, or to cause a denial-of-service (DoS) condition in communication via the unit by receiving a specially crafted SLMP packet

Affected Software

66 affected components
Mitsubishielectric R00cpu Firmware<=19
Mitsubishielectric R00cpu
Mitsubishielectric R01cpu Firmware<=19
Mitsubishielectric R01cpu
Mitsubishielectric R02cpu Firmware<=19
Mitsubishielectric R02cpu
Mitsubishielectric R04cpu Firmware<=51
Mitsubishielectric R04cpu
Mitsubishielectric R08cpu Firmware<=51
Mitsubishielectric R08cpu
Mitsubishielectric R16cpu Firmware<=51
Mitsubishielectric R16cpu
Mitsubishielectric R32cpu Firmware<=51
Mitsubishielectric R32cpu
Mitsubishielectric R120cpu Firmware<=51
Mitsubishielectric R120cpu
Mitsubishielectric R08sfcpu Firmware<=22
Mitsubishielectric R08sfcpu
Mitsubishielectric R16sfcpu Firmware<=22
Mitsubishielectric R16sfcpu
Mitsubishielectric R32sfcpu Firmware<=22
Mitsubishielectric R32sfcpu
Mitsubishielectric R120sfcpu Firmware<=22
Mitsubishielectric R120sfcpu
Mitsubishielectric R08pcpu Firmware<=25
Mitsubishielectric R08pcpu
Mitsubishielectric R16pcpu Firmware<=25
Mitsubishielectric R16pcpu
Mitsubishielectric R32pcpu Firmware<=25
Mitsubishielectric R32pcpu
Mitsubishielectric R120pcpu Firmware<=25
Mitsubishielectric R120pcpu
Mitsubishielectric R08psfcpu Firmware<=06
Mitsubishielectric R08psfcpu
Mitsubishielectric R16psfcpu Firmware<=06
Mitsubishielectric R16psfcpu
Mitsubishielectric R32psfcpu Firmware<=06
Mitsubishielectric R32psfcpu
Mitsubishielectric R120psfcpu Firmware<=06
Mitsubishielectric R120psfcpu
Mitsubishielectric Rj71en71 Firmware<=47
Mitsubishielectric Rj71en71
Mitsubishielectric Rj71gf11-t2 Firmware<=47
Mitsubishielectric Rj71gf11-t2
Mitsubishielectric Rj72gf15-t2 Firmware<=07
Mitsubishielectric Rj72gf15-t2
Mitsubishielectric Rj71gp21-sx Firmware<=47
Mitsubishielectric Rj71gp21-sx
Mitsubishielectric Rj71gp21s-sx Firmware<=47
Mitsubishielectric Rj71gp21s-sx
Mitsubishielectric Rj71c24-r2 Firmware<=47
Mitsubishielectric Rj71c24-r2
Mitsubishielectric Rj71c24-r4 Firmware<=47
Mitsubishielectric Rj71c24-r4
Mitsubishielectric Rj71gn11-t2 Firmware<=11
Mitsubishielectric Rj71gn11-t2
Mitsubishi Electric R00/01/02CPU firmware Versions 19 and earlier
Mitsubishi Electric R04/08/16/32/120(EN)CPU firmware Versions 51 and earlier
Mitsubishi Electric R08/16/32/120SFCPU firmware Versions 22 and earlier
Mitsubishi Electric R08/16/32/120PCPU firmware Versions 25 and earlier
Mitsubishi Electric R08/16/32/120PSFCPU firmware Versions 06 and earlier
Mitsubishi Electric RJ71EN71 firmware Versions 47 and earlier
Mitsubishi Electric RJ71GF11-T2 firmware Versions 47 and earlier
Mitsubishi Electric RJ72GF15-T2 firmware Versions 07 and earlier
Mitsubishi Electric RJ71GP21-SX firmware Versions 47 and earlier
Mitsubishi Electric RJ71GP21S-SX firmware Versions 47 and earlier

Event History

Nov 20, 2020
CVE Published
via MITRE·03:30 AM
Data Sourced
via MITRE·03:30 AM
DescriptionWeakness
Feb 23, 2026
Data Sourced
via ICS·11:57 PM
SeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2020-5668?

CVE-2020-5668 has a high severity rating due to the potential for uncontrolled resource consumption, which can lead to a denial of service.

2

How do I fix CVE-2020-5668?

To fix CVE-2020-5668, update your MELSEC iQ-R Series modules to the latest firmware version as recommended by Mitsubishi Electric.

3

Which versions of MELSEC iQ-R Series modules are affected by CVE-2020-5668?

CVE-2020-5668 affects R00/01/02CPU firmware versions '19' and earlier, R04/08/16/32/120 (EN) CPU firmware versions '51' and earlier, and several other specific firmware versions.

4

Can CVE-2020-5668 lead to system downtime?

Yes, CVE-2020-5668 can lead to significant system downtime due to resource exhaustion if exploited.

5

Is there any workaround for CVE-2020-5668?

Currently, the best approach for CVE-2020-5668 is to upgrade to the patched firmware, as there are no cited workarounds for the vulnerability.

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