Mitsubishi Electric MELSEC iQ-R Series (CVE-2020-16850)

# ICS Advisory (ICSA-20-282-02) ## Mitsubishi Electric MELSEC iQ-R Series Original release date: October 08, 2020 [Print Document](javascript:window.print\(\);) [Tweet](https://twitter.com/share?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-20-282-02) [Like Me](https://www.facebook.com/sharer.php?u=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-20-282-02) [Share](http://www.addthis.com/bookmark.php?url=https%3A%2F%2Fus- cert.cisa.gov%2Fics%2Fadvisories%2Ficsa-20-282-02) ### Legal Notice All information products included in [https://us-cert.gov/ics](/ics) are provided "as is" for informational purposes only. The Department of Homeland Security (DHS) does not provide any warranties of any kind regarding any information contained within. DHS does not endorse any commercial product or service, referenced in this product or otherwise. Further dissemination of this product is governed by the Traffic Light Protocol (TLP) marking in the header. For more information about TLP, see [https://www.us- cert.gov/tlp/](/tlp/). * * * ## 1\. EXECUTIVE SUMMARY * **CVSS v3 8.6** * **ATTENTION:** Exploitable remotely/low skill level to exploit * **Vendor:** Mitsubishi Electric * **Equipment:** MELSEC iQ-R Series * **Vulnerability:** Uncontrolled Resource Consumption ## 2\. RISK EVALUATION Successful exploitation of this vulnerability could result in a denial-of- service condition due to uncontrolled resource consumption. ## 3\. TECHNICAL DETAILS ### 3.1 AFFECTED PRODUCTS The following MELSEC iQ-R series modules are affected: * 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 * R16/32/64MTCPU, all versions ### 3.2 VULNERABILITY OVERVIEW #### 3.2.1 [UNCONTROLLED RESOURCE CONSUMPTION CWE-400](https://cwe.mitre.org/data/definitions/400.html) An uncontrolled resource consumption (CWE-400) vulnerability resulting in a denial-of-service condition may be caused when an attacker sends specially crafted packets to MELSEC iQ-R series modules. [CVE-2020-16850](http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2020-16850) has been assigned to this vulnerability. A CVSS v3 base score of 8.6 has been assigned; the CVSS vector string is ([AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H](https://www.first.org/cvss/calculator/3.0#CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H)). ### 3.3 BACKGROUND * **CRITICAL INFRASTRUCTURE SECTORS** : Critical Manufacturing * **COUNTRIES/AREAS DEPLOYED** : Worldwide * **COMPANY HEADQUARTERS LOCATION** : Japan ### 3.4 RESEARCHER Yossi Reuven of SCADAfence reported this vulnerability to Mitsubishi Electric. ## 4\. MITIGATIONS Mitsubishi Electric plans to release a patch during the coming months, and this publication will be updated with that patch information once available. Please contact a Mitsubishi Electric representative with questions. Mitsubishi Electric recommends users take the following mitigation measures to minimize the risk of exploiting this vulnerability: * Use a firewall or virtual private network (VPN), etc., to prevent unauthorized access if Internet access is required. * Use within a LAN and block access from untrusted networks and hosts through firewalls. CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Specifically, users should: * Minimize network exposure for all control system devices and/or systems, and ensure that they are [not accessible from the Internet](https://www.us-cert.gov/ics/alerts/ICS-ALERT-10-301-01). CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. CISA also provides a section for [control systems security recommended practices](https://www.us-cert.gov/ics/recommended-practices) on the ICS webpage on [us-cert.gov](https://www.us-cert.gov/ics). Several recommended practices are available for reading and download, including [Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies](https://www.us- cert.gov/sites/default/files/recommended_practices/NCCIC_ICS- CERT_Defense_in_Depth_2016_S508C.pdf). Additional mitigation guidance and recommended practices are publicly available on the [ICS webpage on us-cert.gov](https://www.us-cert.gov/ics) in the Technical Information Paper, [ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies](https://www.us-cert.gov/ics/tips/ICS- TIP-12-146-01B). Organizations observing any suspected malicious activity should follow their established internal procedures and report their findings to CISA for tracking and correlation against other incidents. No known public exploits specifically target this vulnerability.