Besen BS20 EV Charging Station Firmware Version Check Manipulation Vulnerability

A vulnerability has been identified in the Besen BS20 EV Charging Station, affecting all versions prior to April 26, 2026. The issue arises from the firmware version check feature, which does not properly validate version responses during update checks. This flaw allows an attacker to intercept and alter the response to indicate a fictitious 'newer' version, thereby enabling the upgrade option even when the device is already up to date. Such manipulation can lead to user interface spoofing and misleading update notifications. The vulnerability can be exploited remotely, although the exploitation process is considered complex and challenging.

Impact

Exploitation of this vulnerability could result in unauthorized user interface modifications, creating false impressions of available firmware updates.

Reproduction

To reproduce this vulnerability, intercept the firmware version check response from the Besen BS20 EV Charging Station. Modify the response to indicate a newer version, then send it back to the device. This can be done using a man-in-the-middle attack approach, such as with a proxy tool that can alter HTTP responses. Once the modified response is received, the device will incorrectly display an available update, allowing for potential UI spoofing.