The past few years have brought forward a bevy of technologies developed in the name of convenience. Internet of Things devices like the Google Home, Amazon's Alexa, or remotely accessible home security devices like Nest cameras and doorbells among them, not to mention the thousands of various doodads, gizmos, and genuinely useful tools that are USB compatible. As of today, you can purchase a high quality, well reputed 128 gigabyte storage device for a little bit over $20 dollars, lightning fast external SSDs for less than $100, or even a portable USB fan to keep you cool during the warm months of the year. The possibilities are endless!
Of course, this massive market of new technologies that are rooted in convenience and comfort isn't without it's faults. The ability for cybercriminals to infect computer systems through the use of USB interfaces is well documented, in fact, the Stuxnet worm that destroyed Iranian uranium centrifuges in 2010 was initially spread through the use of an abandoned, infected USB drive at the Natanz nuclear plant. While Stuxnet turned out to be the work of a highly sophisticated and well-funded nation state threat group, the principal is the same: any device that plugs into your computer, particularly ones that you aren't familiar with, could pose a fundamental threat to your security. There was a huge commotion over the USB fans handed out to reporters -- who likely had tons of sensitive data on their devices -- at the Trump-Kim summit in North Korea last summer. The damage that would be done by having hundreds of reporters plug in malicious USB devices and then bring that malware back to their place of employment boggles the mind.
The only way to prevent these attacks is by educating users of the risks, and by not plugging in devices that you aren't familiar with. That includes phone chargers at an airport or bus station, abandoned USB drives found in a parking lot or at a Goodwill, and even peripherals handed out at conferences and trade shows. Using devices that are purchased from trusted vendors is the only true way to protect yourself from these threats. Once you plug in an unknown device to your computer, it is no longer your computer. Resist the temptation, and don't plug in that USB!