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Edit store price tags using Flipper Zero

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Re: Edit store price tags using Flipper Zero

#311

Post by jojobas »

ssl-3 wrote: post #309
jojobas wrote: post #305

Earlier quoted context omitted.

Well it does need to read individual tag barcodes, so it is indeed one at a time, still you could make an automated camera+beam device, hide at chest level, walk through an aisle as if looking for something, then pick up something in the end of the aisle and go to checkout. I don't think anyone is paying attention anywhere near enough to pick that up. Additionally, one could read some barcodes and make quite cheap ba…

So it needs barcodes to be read? If the lulz are the point, then: Just build hide the thing in the floor-cleaning robot. Include a decent camera (they're very cheap) to catch the barcodes. If the comms last long enough as the machine passes by to program some tags every night, then some tags get programmed every night. Nobody will pay attention to the robot's new purple floodlight in the cameras.

The code mentions composing an address from the barcode, yes.

Shop floor cleaning robots seem to be rather clean on the outside, hard to imagine tampering with one in the field and making it inconspicuous.

Re: Edit store price tags using Flipper Zero

#312

Post by jeroenhd »

weli wrote: post #8

This is pretty dangerous. At least in my country the displayed price must be honored and they cannot refuse the sale.

It's crazy that supermarkets invested in tags without even basic authentication. Hopefully they can sue the manufacturer for the cost of replacing them with moderately secure ones/reflashing the existing tags with secure firmware.

The extreme lack of cybersecurity for something as essential as (often legally binding) price indicators should shock the entire industry, although I feel like it comes to no surprise to anyone actually working on integrating these things.

Re: Edit store price tags using Flipper Zero

#313

Post by jeroenhd »

wyldfire wrote: post #34
weli wrote: post #8

This is pretty dangerous. At least in my country the displayed price must be honored and they cannot refuse the sale.

In your country merchants are not obligated to honor fraudulently altered price displays.

That may not be true if the faked display contents are reasonable. Price labels on shelves are leading: https://www.consumentenbond.nl/juridisch-advies/rechten-bij-...

Supermarkets all throughout my country have these labels add "35% off" to any goods that they need to remove from shelves (either because they expire soon or because they want to replace the product with something different). That's done outside of normal advertising campaigns, just in the price tags on the shelves (and the digital systems, if they actually work).

Supermarkets here are already on thin ice because they frequently do not charge the price listed on shelves already, without malpractice.

Of course, if you happen to have a cart full of wrongly discounted stuff that someone needs to go out and correct, the store will probably look through security footage. If you play the game well and can make it look like a glitch in the system, a store would probably not bother, though.

Re: Edit store price tags using Flipper Zero

#314

Post by jeroenhd »

invalidSyntax wrote: post #278

This is cool and all, but how am I supposed to test it? Get permission at a local store? No way they will let me do it.

You can buy tags like these from the internet, either via shady second hand stores or directly from the same Chinese resellers supermarkets probably use.

Re: Edit store price tags using Flipper Zero

#315

Post by bdavbdav »

ssl-3 wrote: post #261
VorpalWay wrote: post #253

Earlier quoted context omitted.

> Fixed, basic auth would just get leaked (probably first by Home Assistant tinkerers who find some discarded electronic shelf tags somewhere and want a new display for their house). You know what, that is a great idea for a project of mine, where I want to display outside temp and weather forecast in the hallway next to the wardrobe. I have been musing about it for a while now: how to make it small and not stand out…

Just look on eBay. It's full of used electronic shelf tags, sold in bulk -- usually, with prices still on them. :) The sellers don't know anything about how they work so it will take some digging to find the right ones, but having to dig a bit is normal for eBay (or Aliexpress, for that matter).

*was full ;)

Re: Edit store price tags using Flipper Zero

#316

Post by traceroute66 »

> Usually the advertised price must be honored, because it may have brought the customer to your store.

No.

In most jurisdictions this is covered by Contract Law 101 that lawyers learn in year 1.

A contract only forms when you have an offer, acceptance, consideration

The price on the shelf (or shown on the website or in a catalogue) is known as an “Invitation To Treat”.

“Invitation To Treat” means you are inviting the customer to come to you and make you an Offer. There is no obligation on the business to sell.

In the case of a supermarket in the context of this discussion, the agent scans the barcode, and the "real" price is displayed on the screen and added to your bill. This is the "Offer", the business is saying "we are willing to sell you this Tomato at this price, take it or leave it".

If you don't say anything and pay and leave, then "Acceptance" has occured and the "Consideration" is the act of payment itself.

(N.B. IANAL, so my description might not be precicely textbook, but that's the broad concept).

Re: Edit store price tags using Flipper Zero

#317

Post by IanCal »

VorpalWay wrote: post #253
ssl-3 wrote: post #235

Earlier quoted context omitted.

It doesn't really change anything. Previously, a criminal could just print their own shelf tags. They'd probably do this somewhere other than in the store to get the details right, but it was doable. (We've all probably seen rolls of blank shelf tags sitting around at the store, and thermal printers are inexpensive. So what if it's two crimes instead of one?) And then, in the store, they could just switch out the she…

> Fixed, basic auth would just get leaked (probably first by Home Assistant tinkerers who find some discarded electronic shelf tags somewhere and want a new display for their house). You know what, that is a great idea for a project of mine, where I want to display outside temp and weather forecast in the hallway next to the wardrobe. I have been musing about it for a while now: how to make it small and not stand out…

I had a look and knew they seemed to be about £15 here, I couldn’t easily find second hand ones in the uk (though they’re not uncommon at shops). For £40 I can get a 7.5 inch black and white screen setup (trmnl byod xaio https://www.aliexpress.com/item/1005009532501677.html)

Lots of the tags I see though do have Bluetooth or maybe WiFi for updating as well.

I do really like eink things, I want to setup a nice 13 inch one which is now more like £160 so becoming more realistic for my to buy for fun.

I’m going to have to look more into these tags because if there’s cheap second hand ones they’d be awesome.

Re: Edit store price tags using Flipper Zero

#318

Post by lotsofpulp »

kennywinker wrote: post #302
lotsofpulp wrote: post #257

Earlier quoted context omitted.

Retail business profit margins have always been low single digit percentages. More staff can only mean higher prices. I'll gladly scan my own stuff to have lower prices and be able to get out quicker. https://www.macrotrends.net/stocks/charts/KR/kroger/profit-m... https://www.macrotrends.net/stocks/charts/ACI/albertsons/net... https://www.macrotrends.net/stocks/charts/WMT/walmart/profit... https://www.macrotrends.net…

> Retail business profit margins have always been low single digit percentages. And yet overall profits remain high - they’re high-volume low margin businesses. > More staff can only mean higher prices. When you’re talking about massive chains that are prioritizing profits, usually on behalf of shareholders, that is true. For smaller businesses, coops, or even gov run grocery stores - things that aren’t as focussed o…

> And yet overall profits remain high - they’re high-volume low margin businesses.

Why would they not be high? The purchasing power of the currency goes down day after day. If nominal profits are not hitting highs day after day, then you are losing purchasing power.

> It hasn’t matched my experience that prices fell as self checkouts were installed. I think profits went up, prices didn’t come down.

Profit margin is the relevant metric to look at for this context. It is possible prices would have gone up 10% instead of 5% if not for the automation. It is also possible the automation fails to reduce costs.

There are no guarantees in life, just bets that may or may not pan out. Long term trends will the story, but for now, the profit margins make me happy that I don’t invest in grocery stores.

Re: Edit store price tags using Flipper Zero

#319

Post by a96 »

IshKebab wrote: post #41
_joel wrote: post #18

Earlier quoted context omitted.

Are these hacks or cracks. I'd say the latter.

I wouldn't. It doesn't appear that anything was cracked. Rather they just reverse engineered the protocol.

That's a crack, but repurposing price tags to display things they weren't intended to is a hack.

Re: Edit store price tags using Flipper Zero

#320

Post by per1 »

compton93 wrote: post #49
Aboutplants wrote: post #29

I was in college when self checkout became a thing and it took us all of about 45 seconds to realize that you could just check everything out as bananas. Steak was weighed and priced at 4011 (banana code) as the stoned teenager cashier paid no attention. Everything on the receipt was literally Bananas

That's crazy. But coming from someone who wrote a book on retail fraud and worked as a retail fraud analyst for several years... you could have just walked straight out with those items. Transacting was your way of leaving a calling card for the investigators/analysts to find you... You stole regardless of how you did it.

What's the books name?
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