[wilhil]

My fav "abuse" of the system was a car park terminal that was running some flavour of Windows with an antivirus software.

It had a scanner for the barcode of a ticket, but, it understood lots of other barcodes/encoding systems and must have been logging to the filesystem.

So... saw someone encode the EICAR test string to a QR Code and put it to the scanner... that caused the AV to popup which covered the entire screen and made the terminal unusable!

[bagels]

Pretty neat string. A self modifying executable that is also a printable ascii string. https://en.wikipedia.org/wiki/EICAR_test_file

[david_allison]

DEF CON 29 - Richard Henderson - Old MacDonald Had a Barcode, E I E I CAR:

https://www.youtube.com/watch?v=cIcbAMO6sxo

[exikyut]

Got to the point the EICAR string was described as "very, very random" and became abruptly disinterested fwiw.

It's not random. It's a DOS .COM file encoded as printable 8-bit-clean ASCII. The whole point is that it's executable code.

I stopped watching from there so it's possible this was mentioned later in the video.