> 
> On Dec 2, 2023, at 9:52 AM, charles meyer <reachmepl...@gmail.com> wrote:
> 
> Thank you Erich and Thomas.
> 
> I now  have a better understanding of QR codes.
> 
> Is there something I can do to protect the "text" in my QR code?

Not really.  A QR code is just a way to encode information.  In this case, it’s 
a URL, so you sort of have two bits of text (the URL, vs the content at the URL)

> You can imagine how some fraudster might want to manulute or misuse it?

If they’re trying to change your information, for the case where it’s a URL 
pointing to a website they could try to hack the website or screw with name 
arrive to try to serve alternate information, but you have to ask what the 
payoff is for doing this.  If it’s some big name company or government agency, 
maybe there’s reason to do it… for the average person, likely not.

You could of course do something like encode a full vCard in the QR code, but 
then that means you need to give everyone a new QR code when any of the 
information changes, so it removes the ability to have an ‘active’ page of 
information.

> Can I pw protect it?

you can password protect the website that it’s pointing to, but that likely 
defeats the purpose of having a QR code in the first place.


> It might seem cool one day to be able to add graphics (logo) and a live
> link to the QR code but with that comes vulnerabilities.

If it’s an online QR code, yes, that introduces the ability to attack the 
image… but if it’s online, you might as well just have a regular link (which 
could also be attacked), unless the goal is for someone to be able to view the 
page on one device (TV, desktop), and then easily transfer the information to 
their phone.

And technically, the digital image itself has the possibility of being an 
attack vector, as there have been JPEG Library exploits out there.  (I had to 
shut down the server that hosted our project’s ticket tracking software because 
someone had uploaded an image that said ‘I hacked your machine’, and NASA 
security insisted that we had been hacked, but it was because you could attach 
a screen shot with your trouble ticket… but months later, after I had rebuilt 
the server (from original media, re-hardened it, reconfigured everything, went 
through the authority to operate procedures, reloaded the data, waited for the 
shuttle to come down (as no network changes allowed when it was up), got 
everything back online, etc… then months later a virus scanner flagged the 
uploaded file (in a backup partition) as being a Trojan horse)

And adding images to the QR code is no big deal… there are specifications for 
doing so, you just need to find a QR code generator that supports it.

-Joe

(Still no affiliation)
(Unless you could volunteer stuff that has absolutely nothing to do with 
programming and/or libraries)

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