An issue was discovered on Epson Expression Home XP255 20.08.FM10I8 devices. By default, the device comes (and functions) without a password. The user is at no point prompted to set up a password on the device (leaving a number of devices without a password). In this case, anyone connecting to the web admin panel is capable of becoming admin without using any credentials.
Weakness
During installation, installed file permissions are set to allow anyone to modify those files.
Potential Mitigations
- Compartmentalize the system to have “safe” areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
- Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
References