Not necessarily, it should be possible to do this correctly, although I doubt this specific device does so. The device itself needs to be hardened against USB a

Not necessarily, it should be possible to do this correctly, although I doubt this specific device does so. The device itself needs to be hardened against USB attacks, otherwise it would be pointless, of course. Then it copies the contents of the malicious USB stick into a buffer storage, analyses the buffer and cleans up the documents on it, and then it unmounts the first device, mounts the second device and copies the contents of the buffer to it. If it also allows for write-protection, then it might be interesting for forensic work. (AFAIK, USB write protectors cost a few hundred bucks, and maybe this device is the cost range.) The crucial question is, of course, how well the device is hardened against targeted attacks. Just using some seemingly secure Linux won't suffice.