The NCSC is worried about HDMI-based attacks, should you be?

The NCSC is offering an HDMI security device built on its own IP, but security practitioners had mixed reactions on the org's first foray into the hardware market.

The SilentGlass device “actively blocks anything unexpected or malicious between HDMI and Display Port connections and screens”, according to the blog post announcing the product. It's built on NCSC IP licensed to UK firm Goldilock.

Goldilock will manufacture the devices with Sony UK Technology Centre to sell globally. Goldilock and the NCSC did not respond to questions about the price of the devices or further technical details.

Olly Maxwell, principal security operations analyst at Huntress said devices like Silent Glass can "act as an 'HDMI firewall', stripping away those non-essential channels and reducing the attack surface."

However, online commenters questioned the centre's decision to prioritise HDMI cable and monitor security. AppSec security company Cytix co-founder Thomas Ballin went as far as calling the device a “snake oil product.”