▲ ▼ USB Type-C CONDOM
Juice jacking is a type of cyber attack where data is stolen from the electronic devices via USB port when they are plugged in for charging. This has become so common that, Los Angeles' District Attorney's Office published an advisory to travelers about the potential dangers of public USB ports.
This works because data lines on the USB ports are not disabled during charging at the hardware level and often require the users to put their smartphones or other devices to charge only mode. Fortunately there are devices like USB CONDOM which disables the data lines during charging and prevents any form of data transfer thereby preventing juice jacking.
But since Type-C USB devices use the data lines to negotiate voltage with the source; USB CONDOM would limit its function and thereby making the devices charge slower. This is counter intuitive as, we would want the devices to charge faster at a public charging point and there is a need gap.
There are USB-C data blocker available now - https://www.amazon.com/PortaPow-NA-USB-C-Data-Blocker/dp/B082WDHS22/ but the common complaint is slow charging speed.
That indeed addresses this need-gap, The slow charging speed could be because since the voltage couldn't be negotiated it resorts to lowest possible voltage? So in a way there's still need-gap and it's only poised to grow as USB-C becomes ubiquitous.
Good need, In the meantime i would plug in a usbc battery bank (that supports simultaneous charging) between your phone and the charger. Malicious charger doesn't get any info from your battery while a good battery bank is designed to support maximum power delivery from the wall to your phone. You might be able to take apart the battery and utilize just the simultaneous charging logic board but i haven't tried this yet. For me the extra battery outweighs my need for a smaller protection device.
USB-C battery bank with simultaneous charging is indeed a good stop-gap, perhaps one with added protections to detect low-quality chargers and power side-channel attacks could solve this need gap.