[1] As of 2007[update] Miller was a lead analyst at Independent Security Evaluators, a computer protection consultancy.

In 2008, he won a $10,000 cash prize at the hacker conference Pwn2Own in Vancouver, British Columbia, Canada for being the first to find a critical bug in the MacBook Air.

[7] Also in 2009, he and Collin Mulliner demonstrated an SMS processing vulnerability that allowed for complete compromise of the Apple iPhone and denial-of-service attacks on other phones.

As a proof of concept, Miller created an application called Instastock that was approved by Apple's App Store.

[9] Miller, along with Chris Valasek, is known for remotely hacking a 2014 Jeep Cherokee and controlling the braking, steering, and acceleration of the vehicle.