Multiple vulnerabilities in Mitsubishi Electric Air Conditioning System

1) Incorrect Implementation of Authentication Algorithm

EUVDB-ID: #VU54511

Risk: Medium

CVSSv3.1: 6.2 [CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:H/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-20593

CWE-ID: CWE-303 - Incorrect Implementation of Authentication Algorithm

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain elevated privileges on the target system.

The vulnerability exists due to incorrect implementation of the authentication algorithm. A remote authenticated attacker can impersonate an administrator and tamper with information (e.g., operation information and configuration of the air conditioning system).

Mitigation

Install updates from vendor's website.

Vulnerable software versions

G-50A: 2.50 - 3.35

GB-50A: 2.50 - 3.35

AG-150A-A: 3.20

AG-150A-J: 3.20

GB-50ADA-A: 3.20

GB-50ADA-J: 3.20

EB-50GU-A: 7.09

EB-50GU-J: 7.09

AE-200A: 7.93

AE-200E: 7.93

AE-50A: 7.93

AE-50E: 7.93

EW-50A: 7.93

EW-50E: 7.93

TE-200A: 7.93

TE-50A: 7.93

TW-50A: 7.93

CMS-RMD-J: 1.30

PAC-YG50ECA: 2.20

External links

http://ics-cert.us-cert.gov/advisories/icsa-21-182-04

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) XML External Entity injection

EUVDB-ID: #VU54512

Risk: High

CVSSv3.1: 8.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-20595

CWE-ID: CWE-611 - Improper Restriction of XML External Entity Reference ('XXE')

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to insufficient validation of user-supplied XML input. A remote attacker can pass a specially crafted XML code to the affected application and view contents of arbitrary files on the system or perform a denial of service (DoS) attack.

Successful exploitation of the vulnerability may allow an attacker to view contents of arbitrary file on the server or perform network scanning of internal and external infrastructure.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

G-50A: 3.35

GB-50A: 3.35

GB-24A: 9.11

AG-150A-A: 3.20

AG-150A-J: 3.20

GB-50ADA-A: 3.20

GB-50ADA-J: 3.20

EB-50GU-A: 7.09

EB-50GU-J: 7.09

AE-200A: 7.93

AE-200E: 7.93

AE-50A: 7.93

AE-50E: 7.93

EW-50A: 7.93

EW-50E: 7.93

TE-200A: 7.93

TE-50A: 7.93

TW-50A: 7.93

CMS-RMD-J: 1.30

PAC-YG50ECA: 2.20

BAC-HD150: 2.21

External links

http://ics-cert.us-cert.gov/advisories/icsa-21-182-05

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.