CVE-2021-20593: Mitsubishi Ae-200a Firmware

High severity, CVSS 7.1. EPSS: 0.9% chance of exploitation in the next 30 days.

Incorrect Implementation of Authentication Algorithm in Mitsubishi Electric Air Conditioning System/Centralized Controllers (G-50A Ver.2.50 to Ver. 3.35, GB-50A Ver.2.50 to Ver. 3.35, AG-150A-A Ver.3.20 and prior, AG-150A-J Ver.3.20 and prior, GB-50ADA-A Ver.3.20 and prior, GB-50ADA-J Ver.3.20 and prior, EB-50GU-A Ver 7.09 and prior, EB-50GU-J Ver 7.09 and prior, AE-200A Ver 7.93 and prior, AE-200E Ver 7.93 and prior, AE-50A Ver 7.93 and prior, AE-50E Ver 7.93 and prior, EW-50A Ver 7.93 and prior, EW-50E Ver 7.93 and prior, TE-200A Ver 7.93 and prior, TE-50A Ver 7.93 and prior, TW-50A Ver 7.93 and prior, CMS-RMD-J Ver.1.30 and prior) and Air Conditioning System/Expansion Controllers (PAC-YG50ECA Ver.2.20 and prior) allows a remote authenticated attacker to impersonate administrators to disclose configuration information of the air conditioning system and tamper information (e.g. operation information and configuration of air conditioning system) by exploiting this vulnerability.

Affected products

  • Mitsubishi Ae-200a Firmware: up to and including 7.93
  • Mitsubishi Ae-200e Firmware: up to and including 7.93
  • Mitsubishi Ae-50a Firmware: up to and including 7.93
  • Mitsubishi Ae-50e Firmware: up to and including 7.93
  • Mitsubishi AG-150a-A Firmware: up to and including 3.20
  • Mitsubishi AG-150a-J Firmware: up to and including 3.20
  • Mitsubishi CMS-Rmd-J Firmware: up to and including 1.30
  • Mitsubishi Eb-50gu-A Firmware: up to and including 7.09
  • Mitsubishi Eb-50gu-J Firmware: up to and including 7.09
  • Mitsubishi Ew-50a Firmware: up to and including 7.93
  • Mitsubishi Ew-50e Firmware: up to and including 7.93
  • Mitsubishi G-50a Firmware: from 2.50, up to and including 3.35
  • Mitsubishi Gb-50a Firmware: from 2.50, up to and including 3.35
  • Mitsubishi Gb-50ada-A Firmware: up to and including 3.20
  • Mitsubishi Gb-50ada-J Firmware: up to and including 3.20
  • Mitsubishi Pac-YG50ECA Firmware: up to and including 2.20
  • Mitsubishi Te-200a Firmware: up to and including 7.93
  • Mitsubishi Te-50a Firmware: up to and including 7.93
  • Mitsubishi Tw-50a Firmware: up to and including 7.93

Published 2021-07-13. Last modified 2026-06-17.