How to hack TSA Pre-Check
Oct 19, 2012, 12:49 pm
#1
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How to hack TSA Pre-Check
don't do this, it may be a crime.
http://puckinflight.wordpress.com/20...-check-system/
tl;dr
Hack your boarding pass barcode, insert in the pre-check code, photoshop the new barcode on to your boarding pass. Instant pre-check.
http://puckinflight.wordpress.com/20...-check-system/
tl;dr
Hack your boarding pass barcode, insert in the pre-check code, photoshop the new barcode on to your boarding pass. Instant pre-check.
Oct 19, 2012, 1:32 pm
#2
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How to hack TSA Pre-Check
Fail. So now any terrorist with a scanner and printer can get through pre check.
Thanks alot tsa, please just go away
Thanks alot tsa, please just go away
Oct 19, 2012, 1:57 pm
#3
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Wait - if hacking a barcode is this easy for PreCheck, why isn't it just as easy to hack a barcode for the entire boarding pass? Surely they have some sort of encryption or checkdigit equivalent for the barcode that would spit it out as invalid because it doesn't conform to the algorithm.
Oct 19, 2012, 2:05 pm
#4
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It's is a crime and people who attempt this are going to ruin it for others who follow the rules.
Oct 19, 2012, 2:09 pm
#5
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Wait - if hacking a barcode is this easy for PreCheck, why isn't it just as easy to hack a barcode for the entire boarding pass? Surely they have some sort of encryption or checkdigit equivalent for the barcode that would spit it out as invalid because it doesn't conform to the algorithm.
11F>30B
Oct 19, 2012, 2:43 pm
#6
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The text string isn't really what's important, though, it's the barcode that's important, and whether there's some additional bar code validation. I don't know enough about the tech as to how this is done.
Oct 19, 2012, 2:55 pm
#7
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Seat/Gate assignment perhaps?
Oct 19, 2012, 3:02 pm
#8
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Possible. What I did to test the concept was decode the barcode, then take the information I got and re-encode it on another system. The barcode created looked the same as the first. If there was "hidden" data, it should have manifested in the design of the barcode. Though, I admit I am no great shake at understanding the creation of barcode.
I X'd out my seat assignment, and none of those numbers correspond to a gate in PHX.
Oct 19, 2012, 3:03 pm
#9
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You do admit that this is really just a theoretical exercise.
It would be interesting to see if you could print one out from home and also a "real" one from the airport to see what happens when you try to scan it. (not that i'm advocating doing anything potentially illegal)
I would think that they would have thought of something as simple as reverse engineering a string of characters in a barcode and put security measures in place to prevent (or at least make more difficult) potential hacking.
It would be interesting to see if you could print one out from home and also a "real" one from the airport to see what happens when you try to scan it. (not that i'm advocating doing anything potentially illegal)
I would think that they would have thought of something as simple as reverse engineering a string of characters in a barcode and put security measures in place to prevent (or at least make more difficult) potential hacking.
Oct 19, 2012, 3:11 pm
#10
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That said, if the barcode creation program complies with the algorithm for that type of barcode, it should implement any check digits as well, so the point may be irrelevant.
Oct 19, 2012, 3:14 pm
#11
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You do admit that this is really just a theoretical exercise.
It would be interesting to see if you could print one out from home and also a "real" one from the airport to see what happens when you try to scan it. (not that i'm advocating doing anything potentially illegal)
I would think that they would have thought of something as simple as reverse engineering a string of characters in a barcode and put security measures in place to prevent (or at least make more difficult) potential hacking.
It would be interesting to see if you could print one out from home and also a "real" one from the airport to see what happens when you try to scan it. (not that i'm advocating doing anything potentially illegal)
I would think that they would have thought of something as simple as reverse engineering a string of characters in a barcode and put security measures in place to prevent (or at least make more difficult) potential hacking.
Also, by not encrypting the data one can still if they are eligible for pre-check allowing a person to make decision on whether or not to try and "beat the screening" at the airport long before they get to the TDC at the airport. So, even if the one can't modify the data, just by having it visible allows people to beat the system.
All of this could be stopped if the TSA and the Airlines just encrypted the data to begin with.
Oct 19, 2012, 3:14 pm
#12
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You do admit that this is really just a theoretical exercise.
It would be interesting to see if you could print one out from home and also a "real" one from the airport to see what happens when you try to scan it. (not that i'm advocating doing anything potentially illegal)
I would think that they would have thought of something as simple as reverse engineering a string of characters in a barcode and put security measures in place to prevent (or at least make more difficult) potential hacking.
It would be interesting to see if you could print one out from home and also a "real" one from the airport to see what happens when you try to scan it. (not that i'm advocating doing anything potentially illegal)
I would think that they would have thought of something as simple as reverse engineering a string of characters in a barcode and put security measures in place to prevent (or at least make more difficult) potential hacking.
Oct 19, 2012, 3:18 pm
#13
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If the data you put in were the same, the barcode should look the same. If you changed a piece of data, would it look different, and, if so, would it look different in more ways than just the place representing the change you made?
That said, if the barcode creation program complies with the algorithm for that type of barcode, it should implement any check digits as well, so the point may be irrelevant.
That said, if the barcode creation program complies with the algorithm for that type of barcode, it should implement any check digits as well, so the point may be irrelevant.
Now I can't identify some of the data, so it is possible that is CheckSum line that cause the scanner to tell the TSA I am a baddy if I altered it.
Oct 19, 2012, 3:19 pm
#14
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Oct 19, 2012, 3:25 pm
#15
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Perhaps the first test should be with a BP that is simply decoded and recoded? That way if you are asked to print a new one, the encoded digits in fact match on both, then just blame your cheap home printer for screwing up "again."