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Why are so many people being hit with £5 fines for 'counterfeit' stamps?

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Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#201

Post by andrewaylett »

Wingy wrote: post #196
1letterunixname wrote: post #113

Earlier quoted context omitted.

Likely, they use some authenticated hash like HMAC SHA-256 with a schedule of randomly chosen keys added periodically. (Can't really rotate out keys once generated.) GFL reversing the algorithm AND any working key. Also, an "is it used" database has to be kept to prevent an analog replay attack by reusing the same barcode. The most efficient way to keep track of used stamps would be a bloom filter. A poor implementat…

Would pure random + a central database not be more practical? Assuming the barcode is a 10-by-50 grid, that's 500 bits of entropy. With 100 bits of entropy, you need over 100 trillion codes to have a 0.4% chance of a collision. Every added bit makes it twice as unlikely. There's no need to have crypto if you're the authority on both assigning and verifying the barcodes. That way, no attacker will be able to create a…

They're not the only ones creating barcodes -- stamps come with non-specific data, but bulk mailers are allowed to create their own, with embedded routing and billing codes.

The spec is here: https://www.royalmail.com/sites/default/files/Royal-Mail-Mai...

Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#202

Post by Dylan16807 »

boomboomsubban wrote: post #198
Dylan16807 wrote: post #197

Earlier quoted context omitted.

> No, my entire thing has always been based on possession being the crime. Then why did you say "if the law only forbid counterfeiting 100 stamps"?? I'm done too, because my entire argument was based on what you actually said, not what you secretly meant and never clarified. Also the "unless you made them in front of them" excuse about proof could be applied to making even 1. You're grasping at straws to make convict…

This may shock you, but I spent about twenty seconds on my original comment. I certainly didn't have an editor go over it to ensure my actual point of view was getting across. Hell, you can see the edit I made showing when I realized we may be talking past eachother with possess/create.

> I spent about twenty seconds on my original comment.

You then kept defending it.

> you can see the edit I made

Even after that, you were still insisting there were loopholes.

Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#203

Post by boomboomsubban »

Dylan16807 wrote: post #202
boomboomsubban wrote: post #198

Earlier quoted context omitted.

This may shock you, but I spent about twenty seconds on my original comment. I certainly didn't have an editor go over it to ensure my actual point of view was getting across. Hell, you can see the edit I made showing when I realized we may be talking past eachother with possess/create.

> I spent about twenty seconds on my original comment. You then kept defending it. > you can see the edit I made Even after that, you were still insisting there were loopholes.

>Even after that, you were still insisting there were loopholes.

After clarifying my position, I figured you'd either reply with "yes, we were on different wavelengths" or you'd accept we were talking about possession. So when you continued, I assumed you were talking about possession too. My mistake.

Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#204

Post by cyanydeez »

Chris_Newton wrote: post #91

I don’t know whether I should post this as it may be an ongoing case, but not so long ago I sent off my old stamps to the official “swap out” service to have them replaced by the new barcoded ones. A few days later, I did indeed receive equivalent new stamps back — in an envelope that had clearly been tampered with, being roughly cut open all down one side and having the paperwork accompanying the stamps obviously be…

Is england turning into a third world country similar to a far right African state. This sounds like some Mafia stuff.

Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#205

Post by cyanydeez »

LorenPechtel wrote: post #186
karaterobot wrote: post #175

What's interesting to me is that the meaning of 'counterfeit' is being shifted. Counterfeit does not mean actually counterfeit, it means 'we couldn't process this stamp', which is a different thing altogether. I guess that either the Royal Mail's system is failing to read the bar code correctly, or it's encountering a bar code it's already seen before, and assuming it must be malicious. But in the latter case, there'…

I think you're nailing it--some black hat has figured out the encoding and is making fake stamps. Same as gift card draining.

Really sounds more like Mafia interdiction of good stamps and replacement

Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#206

Post by cyanydeez »

taylorfinley wrote: post #59
andrewaylett wrote: post #39

The stamps have "unique" codes, but a genuine counterfeit must still have a code -- and to be useful it must duplicate the code on a real stamp. If the counterfeit gets used first, the stamp is marked as spent, and when the unlucky purchaser of the real stamp tries to use it, they're told theirs is "counterfeit" because it's flagged as "used" in the database?

The barcode in the article decodes to "JGB S11221017031011395940006622112101 BC046285E760466C01" if anyone fancies having a crack at making a stamp keygen.

What's important is it doesn't prevent counterfeit to consumers, which is failed planning.

Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#207

Post by cyanydeez »

1letterunixname wrote: post #113
taylorfinley wrote: post #59

Earlier quoted context omitted.

The barcode in the article decodes to "JGB S11221017031011395940006622112101 BC046285E760466C01" if anyone fancies having a crack at making a stamp keygen.

Likely, they use some authenticated hash like HMAC SHA-256 with a schedule of randomly chosen keys added periodically. (Can't really rotate out keys once generated.) GFL reversing the algorithm AND any working key. Also, an "is it used" database has to be kept to prevent an analog replay attack by reusing the same barcode. The most efficient way to keep track of used stamps would be a bloom filter. A poor implementat…

More likely people (criminals) realized consumers can't protect themselves from near complete fakes and someone's out there making bank.

Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#208

Post by Dylan16807 »

boomboomsubban wrote: post #203
Dylan16807 wrote: post #202

Earlier quoted context omitted.

> I spent about twenty seconds on my original comment. You then kept defending it. > you can see the edit I made Even after that, you were still insisting there were loopholes.

>Even after that, you were still insisting there were loopholes. After clarifying my position, I figured you'd either reply with "yes, we were on different wavelengths" or you'd accept we were talking about possession. So when you continued, I assumed you were talking about possession too. My mistake.

That's why I referred back to "the original", but you misunderstood what I meant there.

Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#209

Post by antifa »

LorenPechtel wrote: post #186
karaterobot wrote: post #175

What's interesting to me is that the meaning of 'counterfeit' is being shifted. Counterfeit does not mean actually counterfeit, it means 'we couldn't process this stamp', which is a different thing altogether. I guess that either the Royal Mail's system is failing to read the bar code correctly, or it's encountering a bar code it's already seen before, and assuming it must be malicious. But in the latter case, there'…

I think you're nailing it--some black hat has figured out the encoding and is making fake stamps. Same as gift card draining.

Wouldn't surprise me if the "encoding" was just unencrypted UUIDs.

Re: Why are so many people being hit with £5 fines for 'counterfeit' stamps?

#210

Post by ffgjgf1 »

rkangel wrote: post #132
rightbyte wrote: post #61

Earlier quoted context omitted.

There was this computer system scandal when lots of post masters were convicted of fraud even though it was known the computer system was buggy. So I wouldn't assume too much competence involved.

That scandal was the Post Office, which is a completely separate organisation from the Royal Mail.

Only since 2011. That scandal started long before that
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