For educational purposes, I will detail the methods attackers can use to create counterfeit transactions in systems without 3D Secure (3DS), explaining why such systems are vulnerable, how these methods work, and what protective measures can be applied. This answer will be structured and detailed to provide a full understanding of the topic, but I will not provide instructions that could be used for illegal activities.
This data is relatively easy to obtain or counterfeit, making systems without a 3DS vulnerable to fraud. Attackers can use a variety of methods to exploit these vulnerabilities. Let's take a closer look.
Example: A fraudster purchases card details on a darknet forum and uses them to purchase electronics on a website without 3DS. The transaction goes through because the store doesn't request an OTP or biometrics.
Why this works: Without 3DS, the card issuer relies solely on the details provided by the store and doesn't verify that the cardholder is actually making the purchase.
Example: A user enters card details on an HTTP website (without encryption). An attacker controlling the cafe's Wi-Fi network intercepts this data and uses it to make a purchase.
Why this works: Without 3DS, there is no additional step to verify the cardholder's identity, and intercepting the data facilitates access to the necessary information.
Example: An attacker obtains a card number and expiration date from a leaked database and uses a script to try CVV codes on a website without 3DS. After several attempts, they find the correct code and complete the transaction.
Why it works: Some payment gateways without 3DS don't block multiple data entry attempts, and banks don't always respond immediately to suspicious activity.
Example: A scammer creates a website offering discounts on electronics. A user enters card details, thinking they're paying for an item. The scammer uses these details to make a purchase on another website without 3DS.
Why it works: Fake websites often look professional and deceive users, and the lack of 3DS makes it easy to use the stolen details.
Example: A fraudster purchases a list of 100 cards on the darknet and tests them by purchasing digital goods (such as subscriptions) on websites without 3DS. Valid cards are then used for larger purchases.
Why it works: Websites without 3DS don't require additional authentication, and small transactions often don't raise suspicions from the bank.
Example: A scammer sends an email, purportedly from a bank, asking the user to confirm card details on a fake website. The user enters the details, which are then used to make purchases.
Why it works: Many users don't verify the authenticity of websites or emails, and the lack of 3DS allows the stolen details to be used without further verification.
Example: A fraudster uses a card number generator to create a card with a valid BIN and a random CVV. They test the card on a website without 3DS, and the transaction is approved due to weak verification.
Why this works: Without 3DS, verification is limited to the data format, and some payment gateways don't check with the issuing bank in real time.
Example: A fraudster enters card details with an incorrect name or address on a website using a weak payment gateway. The transaction goes through because the gateway doesn't verify this information.
Why this works: Some payment gateways are configured to minimize transaction rejections to avoid losing customers, which reduces the level of verification.
If you'd like to delve deeper into a specific method or learn more about technical aspects (such as how 3D Secure works at the protocol level), let me know!
Why are systems without 3D Secure vulnerable?
3D Secure is a security protocol developed by payment systems (Visa, Mastercard, and others) that adds an additional layer of authentication to online transactions. Typically, this involves a one-time password (OTP) sent to the cardholder's phone or email, biometric verification, or a request via the bank's mobile app. Without 3D Secure, transaction verification is limited to the following data:- Card number (16 digits).
- Card validity period (month and year).
- CVV/CVC code (3-4 digits on the back of the card).
- Sometimes the cardholder's name and address (but not always).
This data is relatively easy to obtain or counterfeit, making systems without a 3DS vulnerable to fraud. Attackers can use a variety of methods to exploit these vulnerabilities. Let's take a closer look.
Methods for creating fake transactions
1. Using stolen card data
How it works:- Fraudsters obtain card data through:
- Phishing: Fake websites, emails, or messages that trick users into entering card details.
- Skimming: Devices installed on ATMs or POS terminals that read data from a card's magnetic stripe.
- Data leaks: Hacking of databases of online stores, payment systems, or other platforms where card data is stored.
- Black market purchase: Card data is sold on the dark web for small amounts (e.g. $5–$20 for a full data set).
- Having obtained the data (number, expiration date, CVV), the attacker enters it on a website that doesn't use 3DS. Since there is no additional verification, the transaction can be approved if the data is correct.
Example: A fraudster purchases card details on a darknet forum and uses them to purchase electronics on a website without 3DS. The transaction goes through because the store doesn't request an OTP or biometrics.
Why this works: Without 3DS, the card issuer relies solely on the details provided by the store and doesn't verify that the cardholder is actually making the purchase.
2. Data interception (Man-in-the-Middle, MitM)
How it works:- Attackers intercept card data as it's transmitted from the user to the website. This is possible if:
- The site does not use HTTPS, and data is transmitted unencrypted.
- The user is connected to an unsecured Wi-Fi network where an attacker can intercept traffic.
- Malicious programs (such as keyloggers) are used to record the data entered.
- The intercepted data is then used to make transactions on non-3DS websites.
Example: A user enters card details on an HTTP website (without encryption). An attacker controlling the cafe's Wi-Fi network intercepts this data and uses it to make a purchase.
Why this works: Without 3DS, there is no additional step to verify the cardholder's identity, and intercepting the data facilitates access to the necessary information.
3. Bruteforce CVV
How it works:- If an attacker knows the card number and expiration date (for example, from a stolen database), they can try to guess the CVV code using brute force.
- The CVV is usually 3 digits long (000–999), which allows for a limited number of combinations.
- On sites without 3DS, where CVV verification is minimal, an attacker can automate attempts to enter different CVVs until they find the correct one.
Example: An attacker obtains a card number and expiration date from a leaked database and uses a script to try CVV codes on a website without 3DS. After several attempts, they find the correct code and complete the transaction.
Why it works: Some payment gateways without 3DS don't block multiple data entry attempts, and banks don't always respond immediately to suspicious activity.
4. Creating fake online stores
How it works:- Fraudsters create fake websites that imitate legitimate online stores to collect card data.
- The user enters card details to make a "purchase," but instead of the actual transaction, the data is sent to the attacker.
- This data is then used for transactions on other websites without 3DS.
Example: A scammer creates a website offering discounts on electronics. A user enters card details, thinking they're paying for an item. The scammer uses these details to make a purchase on another website without 3DS.
Why it works: Fake websites often look professional and deceive users, and the lack of 3DS makes it easy to use the stolen details.
5. Carding
How it works:- Carding is the process of verifying the validity of stolen cards by making small transactions on non-3DS websites.
- Fraudsters use automated tools (bots) to test multiple cards by making small purchases (e.g. $1–5).
- If the transaction goes through, the card is considered "live" and can be used for larger purchases.
Example: A fraudster purchases a list of 100 cards on the darknet and tests them by purchasing digital goods (such as subscriptions) on websites without 3DS. Valid cards are then used for larger purchases.
Why it works: Websites without 3DS don't require additional authentication, and small transactions often don't raise suspicions from the bank.
6. Social engineering
How it works:- Fraudsters use psychological manipulation to obtain card details or confirmation codes. Methods include:
- Phishing emails/messages: Fake notifications from a "bank" asking you to enter your card details.
- Calls: Fraudsters pose as bank employees and request card details or codes.
- Fake payment forms: The user is redirected to a fake data entry page.
- The obtained data is used on websites without 3DS.
Example: A scammer sends an email, purportedly from a bank, asking the user to confirm card details on a fake website. The user enters the details, which are then used to make purchases.
Why it works: Many users don't verify the authenticity of websites or emails, and the lack of 3DS allows the stolen details to be used without further verification.
7. Using virtual cards or number generators
How it works:- Fraudsters use services to create virtual cards or card number generators, which sometimes pass verification on websites without 3DS.
- Generators create numbers that match the BIN format (the first 6 digits that identify the bank) and select random combinations for the remaining digits.
- If the site does not check the data carefully, the transaction may go through.
Example: A fraudster uses a card number generator to create a card with a valid BIN and a random CVV. They test the card on a website without 3DS, and the transaction is approved due to weak verification.
Why this works: Without 3DS, verification is limited to the data format, and some payment gateways don't check with the issuing bank in real time.
8. Exploiting vulnerabilities in payment gateways
How it works:- Attackers are looking for vulnerabilities in payment systems or gateways that process transactions without 3DS.
- For example, the gateway may not validate the cardholder's address (AVS) or ignore name inconsistencies.
- Attackers can spoof data or use partially incorrect data that will still be accepted.
Example: A fraudster enters card details with an incorrect name or address on a website using a weak payment gateway. The transaction goes through because the gateway doesn't verify this information.
Why this works: Some payment gateways are configured to minimize transaction rejections to avoid losing customers, which reduces the level of verification.
Additional factors contributing to fraud
- Lack of real-time monitoring:
- Some banks or merchants do not use Fraud Detection Systems (FDS), which analyze transactions for anomalies (such as an unusual location or amount).
- Without FDS, counterfeit transactions may go undetected.
- Weak chargeback policy:
- In systems without 3DS, stores are often held responsible for fraudulent transactions. However, some stores don't dispute chargebacks, making them an attractive target.
- International transactions:
- Fraudsters often use cards from one country to make purchases in another, where checks may be less stringent. Without 3DS, such transactions are more difficult to trace.
Measures to protect against counterfeit transactions
To prevent fraud on non-3DS systems, the following measures can be taken:- Implementation of 3D Secure:
- The most effective method is to use 3DS for all online transactions. This requires additional authentication from the user, significantly reducing the risk of fraud.
- Address Verification (AVS):
- Compare the address provided during payment with the address registered with the bank. This may reveal discrepancies.
- Geolocation check:
- Analyzing the user's IP address and comparing it with the cardholder's location.
- Transaction monitoring:
- Using fraud detection systems that analyze behavior (e.g., transaction frequency, amounts, unusual purchases).
- Transaction limit:
- Setting limits on the amount or number of transactions, especially for new users or cards.
- Request for additional data:
- Request for the cardholder's name, phone number, or other data that is harder to forge.
- User education:
- Educating customers about phishing, the need for HTTPS verification, and the use of strong passwords.
- Using tokenization:
- Replacing card data with tokens that are useless to attackers outside of a specific system.
Conclusion
Systems without 3D Secure are vulnerable due to the lack of additional authentication, allowing attackers to use stolen or counterfeit card details to conduct transactions. Common methods include data theft, interception, brute force, carding, social engineering, and vulnerability exploitation. To protect against this, it's essential to implement 3D Secure, use additional checks and monitoring, and increase user awareness. These measures significantly complicate fraud and make systems more secure.If you'd like to delve deeper into a specific method or learn more about technical aspects (such as how 3D Secure works at the protocol level), let me know!
