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Comment Prototypical example (Score 3, Insightful) 352

Daylight savings is the perfect example of government's regulatory overreach interference in people's lives for theoretical gain. What is there is an increase in stress, time, money and heart attacks.

It's a concept that kills people, something studies have shown for years. Meanwhile anyone who wants an extra hour of daylight can make a personal choice and adjust their sleep schedule.

Comment games (Score 1) 615

init strings
modem connection sounds - and what they meant
DOS memory management
wiring pin outs for serial, parallel and Ethernet cables
null modem cables
IPX/SPX and how to tune the daylights out of it
dip switches

Mind you, many of the above were necessary to do things like play games with your friends. Thinking about it, I learned a lot about networking and hardware because I wanted to play games with my friends and network games were only for the brave. We would hack games that were only supposed to work at the LAN level to work online so we didn't have to haul our computers over every time we wanted to play.

Comment Re:Best feature they could get (Score 1, Flamebait) 47

They do allow hate speech and threats against other peoples lives. Twitters double standards on hate speech are well documented:

When you get to define hate speech as speech that disagree with than everything quickly becomes hate speech.

Comment Best feature they could get (Score 1, Offtopic) 47

By far the best feature that they could possibly get would be remove their political bias. Twitter routinely censors or bans views that don't match their political views. Who seriously thinks excluding a significant portion of the population is a viable business?

Unfortunately they would rather burn their own house down than be politically tolerant. Political correctness strikes again....

Comment Re:It's even easier than that (Score 1) 110

Credit card numbers that long aren't necessary. Changing how they are constructed is. Logically speaking the problem can be fixed (hashing etc.) The problem is that the infrastructure that supports it would also have to be changed and that would be a monumental undertaking. Which is why they are trying to avoid it at all costs. You also have the issue that the typical consumer is not going to tolerate an even longer number than they already have.

The unique credit card number solution has been offered by some banks already (e.g. Amex). Many payment terminals are configured to use DUKPT which creates a unique key per transaction (this is enough to take a cash register out of scope for PCI if properly configured).

You may find this interesting:

Even 2FA is broken if it is done via SMS

Comment Re:It's even easier than that (Score 1) 110

Credit card transactions are fairly well documented (I'm a big fan of DUKPT myself and that is decently documented). However the process used to generate the account and CVC2 numbers themselves is obscure and proprietary to each bank. Most banks do not have the expertise or will to properly perform this function. They count on malicious actors not looking too hard at how they do things.

Unfortunately for the banks once you figure out how to generate these numbers you have broken the primary security used to prevent the public at large from using any given key (card no's) against a very public lock (merchant website). 2FA goes a long way to prevent this!!!

Processors, banks and merchants all have the ability to mitigate this risk by putting in additional controls (geo-location, address, shopping patterns etc.) These all help reduce the risk of a given transaction. However they must balance out approving most (probably legitimate) transactions against an acceptable level of fraud. They must also balance out the overhead involved in reviewing and approving transactions.

The result is the continued use of a system that is fundamentally broken. You will see this type of fraud increase significantly until the whole system is re-engineered.

Comment Re: It's even easier than that (Score 1) 110

Every company chooses their own method of generation for this code. Some vendors use weak encryption, some might use strong encryption, some don't use encryption at all, and some issue the codes in batches. It really all comes down to the company, their risk policies and their expertise. That's why large card dumps are risky, they provide material that can be used to look for patterns. It's a bit scary how many companies have told me they secure their product with base64.

Comment It's even easier than that (Score 5, Insightful) 110

This is a good opportunity to talk about why security through obscurity is bad:

Your typical credit card number has a theoretical 16 digits that are available. That's a huge number (9,999,999,999,999,999) that makes it look effectively impossible to guess. Let's pare that number down to size.

First, you aren't guessing anywhere near 16 digits. It turns out there's a lot you already know (1st digit is 4 for visa, 5 for mastercard etc.). That reduces the typical address space from 16 to 15 digits. That first number turns out to actually just be part of the bank identification number which is typically 6 digits long. All of the rest of it except for last digit is the actual account number. The last number itself is used for a checksum (Luhn) that is used to verify the number is good.

In other words to get the account number right you've only got an address space of 999,999,999. That's a significant reduction in magnitude to start with. Now let's go back to that Luhn checksum (it isn't a hash). Due to this detail you can easily validate the number to make sure that you haven't mistyped it (Luhn precedes using magnetic tape for credit cards).

The Luhn check uses a Mod 10 algorithm that excludes 90% of the previous address space. You now have 99,999,999 numbers to guess against. Your malicious actor isn't starting work in a quadrillion space number, they're working in the millions. All of that is just from the industry standards themselves. Now remember that each bank is going to have their own formulas for generating credit card numbers and that card thieves have data sets of the tens of millions - old dumps are good for providing data that can show patterns. This is a good example of how data at the aggregate level carries risk that it doesn't at the micro level.

Chances are the account number for the card itself isn't at all random. Chances are really good that the formulas used to generate these numbers for a number of large popular banks have been reverse engineered by any number of parties. You also have policies at many banks such as never reusing a number that also reduce this address space. All the malcious actor has to do is look for patterns. Patterns have a way of reducing the order of magnitude once you learn them.

The expiration dates themselves are typically within 2 years giving a range of only 24 to pick from for the typical transaction. Guess a valid account number, try it at 24 websites and chances are really good one of them will work. That leaves the CVC2 number itself, which of course isn't random either.

The system is broken, it's just a matter of time before industry must recalibrate how it works.

More below for those who are curious:

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