Use of a Broken or Risky Cryptographic Algorithm vulnerability in Air Conditioning System G-150AD Ver. 3.21 and prior, Air Conditioning System AG-150A-A Ver. 3.21 and prior, Air Conditioning System AG-150A-J Ver. 3.21 and prior, Air Conditioning System GB-50AD Ver. 3.21 and prior, Air Conditioning System GB-50ADA-A Ver. 3.21 and prior, Air Conditioning System GB-50ADA-J Ver. 3.21 and prior, Air Conditioning System EB-50GU-A Ver. 7.10 and prior, Air Conditioning System EB-50GU-J Ver. 7.10 and prior, Air Conditioning System AE-200J Ver. 7.97 and prior, Air Conditioning System AE-200A Ver. 7.97 and prior, Air Conditioning System AE-200E Ver. 7.97 and prior, Air Conditioning System AE-50J Ver. 7.97 and prior, Air Conditioning System AE-50A Ver. 7.97 and prior, Air Conditioning System AE-50E Ver. 7.97 and prior, Air Conditioning System EW-50J Ver. 7.97 and prior, Air Conditioning System EW-50A Ver. 7.97 and prior, Air Conditioning System EW-50E Ver. 7.97 and prior, Air Conditioning System TE-200A Ver. 7.97 and prior, Air Conditioning System TE-50A Ver. 7.97 and prior and Air Conditioning System TW-50A Ver. 7.97 and prior allows a remote unauthenticated attacker to cause a disclosure of encrypted message of the air conditioning systems by sniffing encrypted communications.