A new dongle has been created to prevent cybercriminals from using the HDMI port as a way to compromise on target endpoints. (Opens in new tab).
The so-called HDMI firewall blocks all communication in and out of the HDMI port that is not directly related to audio or video. Each HDMI port requires a new dongle, but one can be easily reused to fit different ports.
The dongle was designed by a “Kingkevin” who uploaded the project to the source code repository CuVoodoo git.
Change the dongle around
Of course, deploying the dongle will not be an easy task for one without a fair amount of skill.
To use the dongle, one must first program it to fit the port to which it is being applied. This means copying Extended Display Identification Data (EDID) data, including data at supported resolutions. Users can read this data from an endpoint with an I2C-based display data channel (DDC) interface.
The next step is to write EDID data to the EEPROM of the HDMI firewall, which comes with a physically detachable security tab that locks the connector’s EEPROM from future text.
To move the dongle to a new device, users need to re-enable protection by attaching a solder blob across the two pads on the device, rewriting the new port with EDID data, and removing the connecting solder. Two pads
Explained by Tom’s hardware, An HDMI connector allows to passthrough more than just audio and video data. Several parallel protocols are transmitting additional data, including high-bandwidth digital content protection, or HDCP. This protocol ensures that data passing through the port is not copied in transit,
Other notable mentions include Hot-Plug Detection (HPD), and Consumer Electronics Control (CEC). The latter is relatively popular, as it allows remote controls and other gadgets to control devices.
Through Tom’s hardware
