With technology moving on in leaps and bounds daily, it's hard to know how safe your data really is.
This can also call into question how safe you are when you travel, particularly when flying.
Bloomberg's Emily Chang spoke to Bruce Schneier, from Resilient Systems CTO at the Def Con hacking convention in Las Vegas.
See also: World's safest airlines 2015
Schneier says: "Airlines aren't immune to hacking, just like any other industry. We're seeing a lot of attacks against personal information, whether it's by governments or by criminals and we are all vulnerable to this because our data is out there in other people's networks."
When faced with the question of whether these hackers could down a plane, the security technologist said: "That's a different sort of thing entirely, there is research done in the attacking of vehicles... planes are a little bit different."
"Attacking planes remotely seems remote, but as things get computerised and more complicated then we don't know. Hopefully the answer's no."
Qantas was named the world's safest airline for 2015 by AirlineRatings.com.
The airline has topped the charts on a number of occasions and is widely considered the world's most experienced airline.
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