Use of Hard-coded Credentials vulnerability in Mitsubishi Electric Corporation photovoltaic system monitor “EcoGuideTAB” PV-DR004J all versions and PV-DR004JA all versions allows an attacker within the Wi-Fi communication range between the units of the product (measurement unit and display unit) to disclose information such as generated power and electricity sold back to the grid stored in the product, tamper with or destroy stored or configured information in the product, or cause a Denial-of-Service (DoS) condition on the product, by using hardcoded user ID and password common to the product series obtained by exploiting CVE-2025-5022. However, the product is not affected by this vulnerability when it remains unused for a certain period of time (default: 5 minutes) and enters the power-saving mode with the display units LCD screen turned off. The affected products discontinued in 2015, support ended in 2020.
The product contains hard-coded credentials, such as a password or cryptographic key, which it uses for its own inbound authentication, outbound communication to external components, or encryption of internal data.
Hard-coded credentials typically create a significant hole that allows an attacker to bypass the authentication that has been configured by the product administrator. This hole might be difficult for the system administrator to detect. Even if detected, it can be difficult to fix, so the administrator may be forced into disabling the product entirely. There are two main variations:
In the Inbound variant, a default administration account is created, and a simple password is hard-coded into the product and associated with that account. This hard-coded password is the same for each installation of the product, and it usually cannot be changed or disabled by system administrators without manually modifying the program, or otherwise patching the product. If the password is ever discovered or published (a common occurrence on the Internet), then anybody with knowledge of this password can access the product. Finally, since all installations of the product will have the same password, even across different organizations, this enables massive attacks such as worms to take place. The Outbound variant applies to front-end systems that authenticate with a back-end service. The back-end service may require a fixed password which can be easily discovered. The programmer may simply hard-code those back-end credentials into the front-end product. Any user of that program may be able to extract the password. Client-side systems with hard-coded passwords pose even more of a threat, since the extraction of a password from a binary is usually very simple.