high
7.5
CWE
400
Advisory Published
Updated

CVE-2020-5666

First published: Mon Nov 16 2020(Updated: )

Uncontrolled resource consumption vulnerability in MELSEC iQ-R Series CPU Modules (R00/01/02CPU Firmware versions from '05' to '19' and R04/08/16/32/120(EN)CPU Firmware versions from '35' to '51') allows a remote attacker to cause an error in a CPU unit via a specially crafted HTTP packet, which may lead to a denial-of-service (DoS) condition in execution of the program and its communication.

Credit: vultures@jpcert.or.jp

Affected SoftwareAffected VersionHow to fix
Mitsubishi Electric Melsec Iq-R00 Firmware>=05<=19
Mitsubishi Electric Melsec Iq-R00 Firmware
Mitsubishielectric Melsec Iq-r01 Firmware>=05<=19
Mitsubishielectric Melsec Iq-r01 Firmware
Mitsubishi Electric Melsec IQ-R02 Firmware>=05<=19
Mitsubishi Electric Melsec IQ-R02 Firmware
Mitsubishielectric Melsec Iq-r04 Firmware>=35<=51
Mitsubishi Electric Melsec IQ-R04
Mitsubishielectric Melsec Iq-r16 Firmware>=35<=51
Mitsubishielectric Melsec Iq-r16 Firmware
Mitsubishi Electric Melsec iQ-R08 Firmware>=35<=51
Mitsubishi Electric Melsec IQ-R08
Mitsubishielectric Melsec Iq-r32 Firmware>=35<=51
Mitsubishi Electric Melsec IQ-R32
Mitsubishi Electric Melsec IQ-R120 Firmware>=35<=51
Mitsubishi Electric MELSEC iQ-R120

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2020-5666?

    CVE-2020-5666 has a high-severity rating due to its potential for remote attackers to cause significant disruptions to CPU functionality.

  • How do I fix CVE-2020-5666?

    To mitigate CVE-2020-5666, update the affected MELSEC iQ-R Series CPU Modules firmware to a version that is not vulnerable.

  • What types of devices are affected by CVE-2020-5666?

    CVE-2020-5666 affects various MELSEC iQ-R CPU Modules including R00, R01, R02, R04, R08, R16, R32, and R120 with specific firmware versions.

  • Can CVE-2020-5666 be exploited remotely?

    Yes, CVE-2020-5666 can be exploited remotely through specially crafted HTTP packets targeted at vulnerable devices.

  • What are the potential consequences of CVE-2020-5666 exploitation?

    Exploitation of CVE-2020-5666 may lead to uncontrolled resource consumption, resulting in critical operational disruptions for affected CPU units.

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