Anti-fraud features

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The world through the eyes of an anti-fraud

Today I'll tell you why for some time now the antifraud has been looking at us not through rose-colored glasses, but through the scope.

Until recently, the most popular anti-fraud system architecture was the Fraud score architecture. The Fraud score architecture received single parameters and fingerprints using the user's browser, and then, using logical expressions and a statistical base, assigned each obtained parameter or group of parameters a specific weight in the Risc Score, for example:

1. DNS difference from country IP = + 7% to Risc Score

2. The difference between DNS and IP subnet = + 2% to Risc Score

3. Unique Canvas print = + 10% to Risc Score

4. Unique parameters of shaders = + 5% to Risc Score

etc.

As a result of this analysis, the user scored a kind of "Fraud Probability Rating" and, if this rating was below 35%, the protection systems considered all the user's actions legitimate, with a slight increase in the rating, the protection system limited the user's rights, and with a strong increase in the rating, it completely blocked him. There were some exceptions and peculiarities, but on the whole, everything worked like that.

The Fraud score architecture was effective before the advent of advanced antidetect mechanisms and allowed the user to ignore changes in some fingerprints, so very often one could come across statements like "I work from a regular browser, I clean cookies, I use that plugin and everything works for me." Over time, the Fraud score architecture has lost its effectiveness and is being replaced by the more advanced DGA architecture - Dedicated Group Analysis. Most modern anti-fraud systems are based on this architecture.

The DGA uses the same statistical elements as the Fraud score architecture, but the processing logic has been fundamentally changed.

Let's give an example:

Imagine a school with three grades - 1A, 1B and 1B.

We are a cook in this school and we need to understand what food and how much to cook for each of the classes. To solve this problem, we will use the data that was provided to us - these will be names.

1 A class. Students:

Igor, Anton, Sasha, Vova, Gena.

1 B class. Students:

Marina, Oleg, Aristarkh, Sergey, Olga.

1 In class. Students:

Sayfuddin, Yuri, Pavel, Ilya, Maxim.

In order to understand what to cook for each class, we will assign each student a rating from 1 to 9, where 1 is the most "Russian" name and 9 is the most "foreign", and as a result we get:

1 A class. Students:

Igor (1), Anton (1), Sasha (1), Vova (1), Gena (1)

1 B class. Students:

Marina (1), Oleg (1), Evlampy (5), Sergey (1), Olga (1)

1 In class. Students:

Sayfuddin (9), Yuri (1), Pavel (1), Ilya (1), Maxim (1)

Once we have assigned a unique rating to each name, we will compose the overall uniqueness of the class using the standard arithmetic mean function:

1 A class. Rating:

(1 + 1 + 1 + 1 + 1) / 5 = 1

1 B class. Rating:

(1 + 1 + 5 + 1 + 1) / 5 = 1.8

1 In class. Rating:

(1 + 1 + 9 + 1 + 1) / 5 = 2.6

According to the class rating, we will prepare:

For 1 A class - Pies and tea

For 1 B class - Pie and tea

For 1 B class - Echpochmaks and koumiss

Accordingly, we conclude that because of one unique student of Sayfuddin, all other students of grade 1B will suffer, while Sayfuddin will sit with a contented face and drink kumis.

Further, for each class, we will determine the portion size by gender, but here the logic is clear and in grade 1B the portions will be the least because of the two girls.

Translating this example in the context of anti-fraud systems, we conclude that even when all our parameters and prints are changed, but some 1 remains unique (for example Canvas), our overall Risc Score will increase to 26% in DGA architecture systems, while as in Fraud score systems, it would grow by only 10%.

A key feature of the DGA architecture is stricter rules for fraudsters, while not affecting the activities of real users.

The most perfect print. Today, there are many different technologies with which you can identify a user. Some are old, some are new, but combined fingerprints are the best user authentication option. Combined fingerprints are a technique in which a logical expression is used to analyze not one, but two or more parameters of a user's PC, and these fingerprints can reveal information about each other.

Currently the most advanced pair is Canvas-WebGl. Many of you know or at least have heard about these parameters, but almost nothing is known about the method of substituting them, at the same time, it is the method of substituting these fingerprints that hides the most interesting identification mechanisms.

I'll tell you in simple language about Canvas. Modern antidetects for replacing Canvas prints use a simple technology for replacing the color of pixels, that is, when a 2D image of the Canvas technology is drawn, a pixel is selected - the 1st, or 5th, or 125th - (whatever the antidetect developer considers) and in the selected pixel changes color ratio / gamma / transparency. It may not be 1, but 2 pixels, for example, or the 7th or 500th, and a change in color even 1 pixel will change the hash of the print.

*************************************************

What is hash?

Hash is the transformation of an array of data into a single bit string. For example:

Ivanov Ivan Ivanovich 1950 Moscow Nakhimovtsev street 29, apt. 31 +79260014589

converted to hash:

ICAgMTk1MCAgLiAyOSwgLiAzMSArNzkyNjAwMTQ1ODk =

*************************************************

Accordingly, changing the color of the image pixels leads to a change in the Canvas print hash - this is the basis for changing the Canvas print. The question remains why, when using some antidetects, the uniqueness of the fingerprint is 100%, for example, on the browserleaks website. It turns out that antidetects, instead of disguising you, set you apart from the crowd of other users.

I'll tell you in simple language about WebGL. WebGL is a 3D image, first we form a skeleton from vertices and lines, and then we fill the space between vertices and lines with a 2D image. It is important to understand that when building a 3D image, a 2D image is used. To simplify, we end up with Canvas as WebGL.

For those who want to read more deeply:



How WebGL Substitution Works in Modern Antidetects The simplest method of spoofing is the same color change in pixel shaders. In the same way as when substituting Canvas, but in a different place (sometimes substitution of vertex coordinates occurs, but this is an exception). Again, the colors change and again a new hash, the result is achieved and users see the change in the fingerprint, but if there were a public WebGL fingerprint verification service, it would also show the WebGL fingerprint uniqueness equal to 100%. But this is not the worst thing …

But what if we compare the rendering process of these prints? And when comparing the rendering process of these prints, you can see the differences in color formation and, accordingly, identify the use of the antidetect system with 100% accuracy.

The process by which different fingerprints verify each other is a combined browser fingerprint technology.

Here's an example:

1. Launch the Chrome browser

2. In the chrome store, install the DontFingerprintMe developer tool:


3. Open the site facebook.com

4. Press F12 on the keyboard

5. In the toolbar we see the buttons "Elements, Console, Resources, Network" and open the drop-down list >> in it select DFPM

6. Refresh the page facebook.com

7. We see the request for Canvas print

8. Making a login

9. We see the WebGL fingerprint request

Fuck and browser fingerprints

How are browser fingerprints generated?

Our browser fingerprints are not some kind of function put by the developers, and this is not a hidden feature or something like that, there are NO browser fingerprints in the browser!

Everything that we are used to seeing on checker sites and perceive it as prints is actually just a figment of the developer's imagination and nothing more. Let's take a closer look at:

Each browser has a foundation, the foundation is the OS and hardware, in fact, just our PC.

In order to make it convenient for the user to work, the browser transmits information about itself and about the PC to the sites, and even not only in order to make it more convenient to use, but in order to protect itself from "Eblans". Indeed, in fact, 90% of users are complete fucking.

For example:

1. UserAgent

You are looking for a program for yourself, any program you like and go to the site. Here are 4 links - Windows7x32 / Windows 10x64 / MacOS / FreeBsd

And although for everyone who reads this article, the choice is obvious, but most users will not be able to solve this problem on their own and will try to install .dmg in Windows, etc. They need help, so the browser sees your OS and sends data about it to the site - which will automatically give the necessary link and everyone will be happy. Is the browser doing something bad in this case? No…

2. Canvas

Canvas technology is used to render the visual elements of web pages. Until 2006, when surfing the web, to display a web page, the server had to transfer visual elements of the site to our PC - graphics, tables, etc., which heavily loaded the communication channel (remember the speeds of that time) or we had to use Macromedia Flash, to watch videos, or play basic games. But then Canvas came, which is based on JavaScript and now the site does not transfer ready-made elements, but simply shows us the text of the script, which is executed not on the server, but ON OUR PC using our browser and our hardware. The speed has increased, the load on the servers has decreased, the possibilities have expanded. Is the browser doing something bad in this case? No…

Such examples can be given for any technology, and they all boil down to one main goal - to improve usability, and to one side goal - to protect yourself from fucking.

Well, where are our prints then? And fingerprints are just derivatives, in other words, a by-product of event processing.

Example Canvas print:

1. The user visits the site

2. The site transmits javascript to the user's PC by which the user's browser automatically renders a picture with the specified elements, applies effects and shadows (this picture may even be hidden from the user's eyes). The image format is PNG and to generate a PNG image, the library of our operating system called libpng is used, which represents the image in those levels - IHDR, IDAT, IEND (by the way, in IHDR you can directly sign who processed this image and on which PC).

3. The whole picture consists of pixels, and inside the pixel there is chromaticity and transparency, so the picture is serialized into a byte array.

4. The byte array is encoded in base64 format and transmitted to the site

5. The site uses hashing technology or does not (depends on the developer) and receives our pseudo-unique Canvas fingerprint - here it is, our fingerprint!

What is the uniqueness of a print and why is it so important?

Many people know the site: https://browserleaks.com/canvas

And probably everyone is interested in why the site detects my operating system from a real PC, but not from an antidetect and shows 100% uniqueness.

If you do not resort to secret Masonic technologies, you can simply guess, the Browserleaks site records the users who visit it and the user agent records it, comparing it with the canvas - that's all. At the time of this writing, the number of user agents in the Browserleaks database was 358283. But this is just a small site known only to a narrow circle of people, but imagine a statistical collection of Google, or Facebook, or Betfair or Paypal.

Resources with millions of hits per day can in the simplest way collect internal statistics and compare that your unique fingerprint has not been used by any of the 100,000,000 users in the last year. Where will this lead you? And this will lead you to the effect of an ostrich - when your head is in the sand (I checked everything on browserlix, I have all the fire!), But your butt will be outside and will set you apart from the crowd of all other ostriches, because the benefits of 100% uniqueness of the print are the same a myth like the myth about the head of an ostrich in the sand.

But besides the fact that the fingerprint will set you apart from the crowd of other users, it will also harm the rest of your fingerprints …

Do you know why antidetects die?

Let's imagine a pristine payment system and a carder.

The carder enters this system from his real PC (don't forget about the fucking guys) and steals money. The system will allow him, but then it will work on the errors and understand that the user with such prints is a fraud and the second time he will not be allowed to steal money.

Carder will go and buy an antidetect - all the prints are new, everything is ok and again he will be able to steal money, and then change the prints and steal again, etc. But after a while, the system, applying machine learning, artificial intelligence and voodoo rituals, will develop the following policy:

UserAgent valid check:

1. HTTP Header - Chrome

2. Browser signature - Chrome

3. DynamicCompressor - Chrome

4. Mime Types - Chrome

5. ClientRect - Chrome

6. Canvas - UNKNOWN

And after analyzing the thefts that took place, the system will conclude that when using a unique canvas and it is not possible to match it with the OS version, all users with such data must enter the SECURITY MEASURE restriction.

What the anti-fraud system did is called the independent application of the logic of protection technologies based on statistical data. And if it is simple - they followed, followed and took the ass.

Examples of independent implementation of protection algorithms are based only on the analysis of the actions that have taken place and only then are introduced as frontal protection mechanisms in systems based on the DGA architecture - Dedicated Group Analysis (it was discussed in the first part).

However, anti-fraud systems have a few more aces up their sleeve, one of which is called Fuzzy Hash or fuzzy hashing.

Here's an example:

Ivanov Ivan Ivanovich 1950 Moscow Nakhimovtsev street 29, apt. 31 +79260014589

converted to hash:

ICAgMTk1MCAgLiAyOSwgLiAzMSArNzkyNjAwMTQ1ODk =

This is exactly how our prints are converted - into one single hash. And what happens if Ivan Ivanov changes his phone number?

For example:

Ivanov Ivan Ivanovich 1950 Moscow Nakhimovtsev street 29, apt. 31 +79260014588

converted to hash:

ICAgMTk1MCAgLiAyOSwgLiAzMSArNzkyNjAwMTQ1ODkKCg ==

Having changed only 1 digit in the phone number, we already have a new hash and a new identity, but has the essence of Ivan Ivanov changed? No, it hasn't changed. What should be done in this case?

To solve this problem, the phasing hashing technology is used, which allows you to ignore the set% changes until the collected data is converted into a hash.

In simple terms - if Ivanov Ivan Ivanovich changes his phone or city, street or apartment - we will still recognize him. The antifraud system acts in exactly the same way, collecting information about you and comparing it with the existing one. This is an excellent mechanism for calculating carders, fraudsters, etc., who, using an antidetect, can "bypass" only the protection of the Browserleaks site.

In simple words, if your antidetect produces unique fingerprints, for example, Canvas - throw it away. This is shit.
 

WHAT DOES ANTI FRAUD LOOK AT WHEN CARDING?​


Carders, hello!

I had very little time to search and write articles. Lots of work, lots of orders, lots of jobs. But today I prepared the fit for you.

This article will be like an Alma mater for beginners, so sit back and read the following information carefully.

We will disassemble everything in order from A to Z and we will start with the first acquaintance of the shop with YOU. Basic information only applies to stuff carding and USE work.

System Definition:

As soon as you click on the link to the site, the anti-fraud immediately scans the indicators of your hardware, the main ones are:
  • UserAgent is a client application that uses a specific network protocol (more on wikipedia).
  • Browser + version
  • System Language + Keyboard Layout Language
  • Color Depth - The color depth of the monitor.
  • Screen Resolution
  • Time Zone
  • Is the session saved in the browser
  • CPU class
  • Iron platform (more on wikipedia)
  • DoNotTrack enabled or not
  • A complete list of installed fonts (maintaining their order, which increases entropy), implemented with Flash.
  • List of installed fonts detected by JS / CSS (side channel method) - can detect up to 500 installed fonts without flash
  • Canvas fingerprint
  • WebGL Fingerprint
  • Are plugins and addons installed, if so which ones
  • Is AdBlock worth it or not
  • Touchscreen detection and capabilities
  • Pixel Ratio
The source from where you went to the site and the link itself are also important, since it is often with utm tags . That is, a direct transition from google by the name of the site does not give you privileges, the transition to a search query for a certain product or the transition from sites with coupons to this shop will be appreciated.

IP Address:

An important indicator for anti-fraud is your ip and dns addresses, the presence of an IP address in the black lists, your ping, proxy score, risk score (from maxmind).

Proxy Score
- the probability of using a proxy

Risk Score is an indicator of the number of fraudulent operations from a given IP address.

The less these indicators and the cleaner your ip, the less fraud points you get.

But again it depends on what you are working with. If you plan to work with a PayPal: logs, self-registers, brutal, then black lists, for example, do not play any role. IP geolocation also does not affect. Its quality and naturalness of the system affect.

Warm-up Shop:

All shops, except for the most leaky ones, use cookies and this also affects success of carding. For example, you have 50+ Microwave search results in your cookies, but you go to Amazon to order the latest iphone model. Fraud will be increased for such an order. If you look for the same Microwave, the loyalty of the fraud to you will be higher.

Before carding, you need to warm up the shop (fill in cookies), imitate the usual actions of the buyer, for example: climb through the categories of interest, look for the product you need from different manufacturers, read reviews for each product and leave feedback about them whether the review was useful or not, check the characteristics several products, read the rules and privacy policy of the site, if possible, chat and scroll through the faq, while the last steps should be done after you have filled cookies with the search for the product you need.

After we have warmed up the shop for 15-60 minutes (depending on the fraud of the shop, respectively), we either let the account rest by saving all the cookies and go in 3-4 hours or after 2-3 days to place an order, or proceed to the order immediately (depending on carding amount + antifraud complexity).

Large shops like amazon also look at the account registration date and purchase history. Therefore, the probability of immediately carding an expensive product is close to 0 (brute without warming up)

Carding process:

As soon as we have warmed up the shop and decided on the product that we will order, go to the checkout page and register on it (preferably if we do it later) or continue as a "guest".

We enter our billing and shipping addresses and then select the payment whether it is CC (Credit Card) or stick (Paypal) and proceed with the payment.

Now let's figure out what the antifraud fires on the checkout page:
  • Distance between billing and shipping addresses. The greater the distance, the more fraud points.
  • Shipping differs from Billing - there are shops that are not sent to a different address from billing and your order is automatically canceled. If it hisses, then the distance between the addresses is taken into account, that is, if you carding from New York to Los Angeles, then most likely such a pack will be canceled or the dialer will have to come up with a story. This all applies to the work of usa, in Eu the rules are different.
  • Order amount (each shop has its own average check, which is the norm)
  • Number of positions.
  • Liquid goods and popular sizes, colors - that is, if we order XXL size panties from Sale, then there will be no fraud points, but if we order a L size jacket from the BESTSELLING category, then it is clear that they will be. But these are little things and are far from the main reason for the success / failure of carding.
  • The number of attempts at a successful transaction - that is, if you entered 10 cards in a row and you did not carry out a transaction - accordingly, you are credited with fraud points.
  • The domain of your email. You need to use the mailbox of the same country as the shop, or use gmail. Better than the same country.
Attention! If the merchant of the shop is with AWS, then the billing address that you entered on the site and the billing address on the map is verified accordingly. If you carding with EU material, where no AWS, then the antifraud will display that it was not possible to reconcile the billing - this will usually transfer the order from auto processing to manual verification and the manager, starting from the fraud points, will decide whether to send the pack or not.

I hope this article turned out to be informative and useful for you!
 
Antifraud is your enemy!

5845e1620df7c0a338a01.png


Halo, carder! Did you miss me? Don't get me wrong. I have a lot of things to do, I try to do everything in time, and today I finally prepared an article for you.

97c39c372579e8cf6ed3a.png


Antifraud is a system for detecting and combating fraud when IT users use e-commerce systems.

To put it more clearly, this is a system that checks you for similarity with the CH (cardholder).

How exactly does the anti-fraud system work?
So, you wanted to buy something in an online store. You add a product to your cart, write your address, etc. It comes to payment. You enter the data of your own (or someone else's, if you are a true carder) card. And then comes the antifraud.

All the data you transmit, and there are a lot of them, such as your IP address, OS and browser information, cookies, location, payment data itself, etc. are subject to strict analysis.

Anti-fraud-the system analyzes the information to decide whether to skip this transaction or send it to the fuck.

Anti-fraud-the system processes the payment, evaluates its risk, and if necessary, launches additional verification methods (such as manual verification or additional identification of the cardholder, such as a call to the phone from the bank) and sends back its decision.

As a result, the transaction either passes or does not.

How to get around it?
Be like a cardholder.

What do you think, will the cardholder pay from a Russian IP address to the wrong address? I think not, antifraud does not allow such things.

Therefore, under the account of the state of Florida's eBay, you need to buy a dedic / tunnel /socks of Florida State, this will remove the first suspicions. Next, you need to find drops and then you can beat them. Also check your anonymity on the site whoer.net and similar ones should be at least 80%. However, your dns can still burn you down, so I advise you to use the dnscrypt software, which will replace it. And don't try to use any VPN.

The main rule of good carder is to think like a CH, that is, do not beat with an ip address from acc USA somewhere in the Russian Federation, do you think the SB of the shop in which you are trying to drive in stupid ones and you will deceive them?

This isn't 2010, when everyone was a mammoth!
Quotes from great people xD

Now is the time to think. Do not forget that it is better to drive during the lunch break CH, as they have everything on time, and neither do we plow like a slave without breaks and weekends! That is, if you drive in during lunch, then the probability of bypassing antifraud is greater. Imagine how many people make purchases on eBay at this time ? So you have a chance to get lost at this time.

Of course, these are not all points for circumventing anti-fraud.

Remember that the most important thing is to set up the system correctly and disguise yourself as some lucky Michael from Miami who wants to buy something for himself on the Internet...

Anti-fraud systems are constantly evolving, but we are not standing still.
 
Analysis of Anti-fraud errors
01 Refer to card issuer
02 Refer to card issuer (You need to call the bank to complete the transaction)
03 Invalid merchant
04 Pick-up card
05 Do not Honor
06 Error (Unknown bank side error)
07 Pick-up card, special condition
12 Invalid transaction card / issuer / acquirer (Merchant does not accept cards from this bank)
13 Invalid amount
14 Invalid card number (Invalid card number or the card is blocked by the holder, bank)
19 System Error
21 No Action Taken
34 Suspected Fraud
39 No Credit Account
41 Lost Card, Pickup
42 Special Pickup
43 Hot Card, Pickup
51 Not sufficient funds
54 Expired card
55 Incorrect PIN
57 Transaction not permitted on card (Merchant does not accept cards of this bank)
58 Txn Not Permitted On Term
59 Suspected Fraud
61 Exceeds amount limit
62 Restricted card
63 Security violation
75 Exceeds PIN Retry
78 Function Not Available
82 CVV Validation Error
91 Issuer not available
93 Transaction violates law
94 Duplicate Transaction
96 System Error
 
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A man invented a wheel, and an antifraud how to insert sticks into wheels.
Anti-fraud systems by attributes and signs of transactions are trying to detect fraud (fraudulent transactions, illegal access, and everything that we love so much). There are a lot of such systems on the market, including the Russian market. These are, for example, NICE Actimize, Eye4Fraud, SecureBuy Phoenix FM, RSA Adaptive Authentication, IRIS Analytics (IBM), Fraudwall and many others. But this is of little interest to us, because

A) Your systems differ from foreign ones in the same way as the methods of conducting and confirming transactions.

B) Most of the structures of interest to us use self-written af

To win in a difficult battle, you need to know about the enemy what he does not know about himself. Therefore, let's dig deeper.

Fantastic Beasts and What's Inside
Since the price of this online alarm is indecent to such an extent that it would never occur to anyone to drain the algorithms of its operation, all systems operate according to the Black box principle. Something you can reach with your own mind, for example, it is obvious that one of the most effective technologies is machine learning modules. When the system, based on the analysis of the actions of fraudsters, potential fraudsters and honest carders, draws "conclusions" and adjusts the algorithm to the specifics of the behavior of these persons. But for the giants of the af-systems market, the basic modules practically do not differ, and among them there are always:

Filter validators. An example is a validator of bank card details. Already in the process of entering on the payment form, the card number is checked by the system, and thus it makes sure that the buyer has not sealed it, and the card number entered on the payment form is correct. By the first digits, it determines the issuer of the card (belonging to the bank that issued it). Yes, map generators have not been relevant for 10 years already.

Geographic filters. For example, by country of IP addresses. Accessing the geolocation of your device, the system checks the entered data (address of residence / place of issue of ssn / dl and other identification documents, and even RN from the base) for compliance with the current location. Plus, geographic filters are the latest Nazis. They cut off access to residents of third world countries (while they are rising from their knees), because statistics show that in some African countries there is a high level of skimming and compromise of cards, and, as a result, payments made from these countries are highly likely to be fraudulent. At the sight of the CIS-ip in the server room, where the af is, the siren must be howling.

Stop-list filters. If the system receives the data of a card on which payments have already been made marked "Fraud", or the cardholder has notified the issuing bank about the compromise of its data, such a card is included in the stop list - the system knows that transactions cannot be skipped on it, since they will turn out to be fraudulent.

Authorization limit filters. For example, the limit for the amount of one transaction, the number of authorization attempts from one IP address or from one bank card. To protect both the payer and other participants in the online payment process, there are restrictions on the number and amount of payments made during the day or other period. And there is also such a thing as a behavioral factor. If a man took anorexic women to a restaurant all year long, who ordered only water for themselves, and then got on a lady with gastronomic preferences from the category of "white truffle for a snack", most likely, the bill will have to be paid in cash. Transactions that differ from the ones usually carried out by this cardholder by at least $ 1k are suspicious.

In order to gain confidence in antifraud, you need to set up your working machine. If this is a PC, you need to run English Windows on it, use only one keyboard layout, change the time zone, clear cookies and system logs, replace ip, dns, monitor their leakage, and each time change all this + system parameters. I'll tell you about this a little later in all colors.

Among other things, such modules as AVS - reconciliation and 3D-secure are widespread in the US.

AVS - reconciliation of billing and shipping addresses in shops. Billing is the address from the card, shipping is the specified shipping address, in our case it is a drop, middle or stingy. You won't be able to send it to another shipping with an ABC, the only way out is to drive it into cardholder and be ready to fork out for a reroute or a pickup.

3D Secure is a security protocol that will request a cvv2 code (in common people vbv) or sms. If he doesn't like you at all, he will ask for both. But if the vbv is not provided on the map itself, there will be no questions for you, so use the bins without the vbv.

Well, where is the same without two-factor authentication. On exchanges, this is usually a code from a flash drive or from a Google authenticator; in banks - secret questions; in payment systems - a code either from SMS or from a letter to the mail.
 
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