Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2021.1389.2 Advisory (icsa-21-112-02) Mitsubishi Electric GOT 30 July 2021 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Mitsubishi Electric GOT SIMPLE series products Mitsubishi Electric GOT2000 series products Operating System: Network Appliance Impact/Access: Unauthorised Access -- Remote/Unauthenticated Resolution: Patch/Upgrade CVE Names: CVE-2021-20590 Original Bulletin: https://us-cert.cisa.gov/ics/advisories/icsa-21-112-02 Revision History: July 30 2021: Vendor updated advisory with update details April 23 2021: Initial Release - --------------------------BEGIN INCLUDED TEXT-------------------- ICS Advisory (ICSA-21-112-02) Mitsubishi Electric GOT (Update A) Original release date: July 27, 2021 Legal Notice All information products included in https://us-cert.cisa.gov/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://us-cert.cisa.gov/tlp/ . 1. EXECUTIVE SUMMARY o CVSS v3 5.9 o ATTENTION: Exploitable remotely o Vendor: Mitsubishi Electric o Equipment: GOT o Vulnerability: Improper Authentication 2. UPDATE INFORMATION This updated advisory is a follow-up to the original advisory titled ICSA-21-112-02 Mitsubishi Electric GOT that was published April 22, 2021, on the ICS webpage on us-cert.cisa.gov. 3. RISK EVALUATION Successful exploitation of this vulnerability may allow an attacker to gain unauthorized access. 4. TECHNICAL DETAILS 4.1 AFFECTED PRODUCTS Mitsubishi Electric reports the vulnerability affects the VNC function of the following devices: - --------- Begin Update A Part 1 of 2 --------- o GOT2000 series GT27 model: VNC server Versions 01.39.010 and prior GT25 model: VNC server Versions 01.39.010 and prior GT21 model: GT2107-WTBD: VNC server Versions 01.40.000 and prior GT2107-WTSD: VNC server Versions 01.40.000 and prior o GOT SIMPLE series GS21 model GS2110-WTBD-N: VNC server Versions 01.40.000 and prior GS2107-WTBD-N: VNC server Versions 01.40.000 and prior To check the version in use, please refer to the user's manual available from the Mitsubishi Electric FA Global website . - --------- End Update A Part 1 of 2 --------- 4.2 VULNERABILITY OVERVIEW 4.2.1 IMPROPER AUTHENTICATION CWE-287 A password authentication bypass vulnerability exists in the VNC function of the GOT2000 series and the GOT SIMPLE series due to improper authentication. CVE-2021-20590 has been assigned to this vulnerability. A CVSS v3 base score of 5.9 has been calculated; the CVSS vector string is ( AV:N/AC:H/PR:N/UI:N/S:U/ C:N/I:H/A:N ). 4.3 BACKGROUND o CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing o COUNTRIES/AREAS DEPLOYED: Worldwide o COMPANY HEADQUARTERS LOCATION: Japan 4.4 RESEARCHER Mitsubishi Electric reported this vulnerability to CISA. 5. MITIGATIONS - --------- Begin Update A Part 2 of 2 --------- Mitsubishi Electric instructs users to restrict access to the product only from trusted networks and hosts until they can update to one of the following fixed versions: o GOT2000 series GT27 model: VNC server Version 01.40.010 or later GT25 model: VNC server Version 01.40.010 or later GT21 model: GT2107-WTBD: VNC server Version 01.41.000 or later GT2107-WTSD: VNC server Version 01.41.000 or later o GOT SIMPLE series GS21 model GS2110-WTBD-N: VNC server Version 01.41.000 or later GS2107-WTBD-N: VNC server Version 01.41.000 or later Please refer to the Mitsubishi Electric website for details and update procedures. - --------- End Update A Part 1 of 2 --------- CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. Specifically, users should: o Minimize network exposure for all control system devices and/or systems, and ensure they are not accessible from the Internet . o Locate control system networks and remote devices behind firewalls and isolate them from the business network. o When remote access is required, use secure methods, such as virtual private networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize a VPN is only as secure as its connected devices. 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 on the ICS webpage on us-cert.cisa.gov . Several recommended practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies . Additional mitigation guidance and recommended practices are publicly available on the ICS webpage on us-cert.cisa.gov in the Technical Information Paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies . 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. This vulnerability has high attack complexity. For any questions related to this report, please contact the CISA at: Email: CISAservicedesk@cisa.dhs.gov Toll Free: 1-888-282-0870 CISA continuously strives to improve its products and services. You can help by choosing one of the links below to provide feedback about this product. - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: https://www.auscert.org.au/bulletins/ =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBYQOCD+NLKJtyKPYoAQiG1RAAjAZrLc2vh5uQQUfc2vDmr9Vhiq4qd2ig dyAB8xkZnkpbhD8sQLSdyAIgX+LSzK94kGJXj8Cr9+D8Yp+aHPdFF0L1b0PGtgp9 FslzO3wG1l4vz724CjxccJUuExzhmhpoD5qsnjIoTyYw7uv70Lyqk6mNhikIRHZ0 85SRCL/AtkmBXaR53OpQwCfT6ZGC4Z06pqHtudYCzAnu9x+kqFYOJTewn4CMNJvn o1xan1E91mmhrCfx2UeHUPFxcunAHuctq4NeMQMbDE7IB7bY2zqgjhspCk3tNSY3 nMKOvV0/xbLVRXRslszwzZOw943pmIXTP3ppbPWIm9gB6xHPQ5iWut9wUbspznTc tGRz6aJxz/IMtQtlc3nsgljx3mBs8BPEli2VRyleNrZeWHuMjaqibs59eA1SJSvd aRRkmpqi5Sn3ytZGtY8XsymgsMoyXMNeODpsP84Fduisq4uJhJBoXrc/a5jmgdAi LmlytyJW/WjF55gLzruW1hQcpbmu2s8Q2s2YTQkcXlE/7FaU7DauPQGpQoRcCXMk fwGeFCRFe/IPsWbdAdMl+h6TPgXAa5+qk0DdDrEOru/Srjq4FBJouc119FRYyJaZ rESZcGJ5LqomgYfO8mTutQMp3RADviMDP8r74xdNfNq4i79ERZIDjYJkImMg/+kW WbzT3X5CcCE= =y0r+ -----END PGP SIGNATURE-----