Edward Snowden wants you to know at all times whether the NSA is keeping tabs on your iPhone.
Along with Andrew Huang, his coauthor and fellow hacker, Snowden presented his research on phone “hardware introspection” at MIT, which aims to give users the ability to see whether their phone is sending out secret signals to an intelligence agency.
“This work aims to give journalists the tools to know when their smart phones are tracking or disclosing their location when the devices are supposed to be in airplane mode,” the pair wrote in their technical paper.
Snowden, an ex-NSA contractor living in exile in Moscow, and Huang, a prominent hacker who has reverse-engineered the Xbox and other hardware, believe that their solution can protect journalists and activists from being betrayed by their smartphones.
In their paper, they mention Marie Colvin, a journalist who was killed by Syrian forces in 2012. A 2016 lawsuit against the Syrian government alleges that her cellphone signals were intercepted and she was deliberately targeted.
Your phone is lying to you
In their paper, Snowden and Huang make it clear that what you see on your phone’s screen is not always true.
If you turn off Bluetooth or cellular service, then the phone’s radios and other electronics can still be made to send signals, especially if they are compromised by a sophisticated intelligence agency or hackers. Even airplane mode isn’t a defense, since the current version of Apple’s iOS still keeps the GPS active while in that state.
“Trusting a phone that has been hacked to go into airplane mode is like trusting a drunk person to judge if they are sober enough to drive,” they write.