Banking Data Breaches: The Fraud You Didn’t See Coming

Your customers are panicking. Unauthorized transactions have drained accounts, credit card charges are piling up, and fraud alerts are triggering across multiple banking systems. Your security team scrambles to assess the damage, but the attackers are already steps ahead. How did this happen? To truly understand, we must work backward, unraveling the breach from its disastrous aftermath to the missed warning signs hidden in your network.

As we dissect each stage of this attack, we’ll explore how network logs, a common network detection and response (NDR) data type, provided limited insights and how packet data could have delivered the intelligence needed to detect and stop the fraud before it escalated.

Step 1: The Fallout

What Happened

Customers are reporting unauthorized withdrawals, wire transfers, and credit card fraud. Call centers are overwhelmed, regulators are demanding answers, and trust in your institution is eroding. Attackers successfully executed account takeovers (ATOs), draining funds and executing fraudulent transactions.

• What logs provided: Logs showed multiple login attempts and transaction requests, but they lacked the context of how attackers bypassed authentication and manipulated banking sessions.
• What packet data could have provided: Packet data would have revealed session hijacking techniques, fraudulent API calls, and manipulated banking traffic, giving security teams the ability to detect and disrupt the attack before funds were lost.

Step 2: The Unauthorized Transactions

What Happened

Once inside, the attackers used stolen credentials and session tokens to initiate wire transfers and fraudulent payments. By the time fraud detection systems reacted, millions already had been transferred.

• What logs provided: Logs identified high-risk transactions and flagged unusual payment behaviors, but they couldn’t determine whether transactions were authorized or manipulated through session hijacking.
• What packet data could have provided: Packet data would have captured the exact manipulation methods used, such as man-in-the-middle (MITM) attacks or API injection, helping analysts identify fraudulent behavior before the transactions were finalized.

Step 3: The Account Takeover

What Happened

Attackers leveraged phishing, credential stuffing, and password resets to compromise customer accounts. Once inside, they escalated privileges and disabled security notifications to avoid detection.

• What logs provided: Logs captured failed login attempts and IP changes but couldn’t distinguish legitimate users from compromised sessions.
• What packet data could have provided: Packet data would have exposed session anomalies, multifactor authentication (MFA) bypass techniques, and fraudulent authentication methods, allowing security teams to disrupt takeovers before the financial loss occurred.

Step 4: The Initial Compromise

What Happened

The attack began when attackers exploited a vulnerability in the bank’s online banking platform. A misconfigured API allowed them to bypass authentication controls, gaining direct access to customer accounts without requiring stolen credentials.

• What logs provided: Logs recorded unusual API requests and login patterns but couldn’t determine whether the access was legitimate or malicious.
• What packet data could have provided: Packet data would have exposed unauthorized API calls, session token manipulation, and the exact payloads used to exploit the vulnerability. This enables security teams to detect and patch the flaw before widespread exploitation.

What Could Have Been Done?

At every stage of this breach, packet data provided the depth of insight that logs couldn’t. Although logs summarize events, packet data delivers the raw truth, showing attackers’ actions in real time, revealing unauthorized transactions, and exposing fraud techniques.

Could This Happen Again?

Banking and financial institutions are prime targets for fraud, ATOs, and sophisticated cyberattacks. This isn’t a matter of if it will happen again, but when.

Will You Be Able To Stop It in Time?

Learn how NETSCOUT Omnis Cyber Intelligence provides financial institutions with real-time network visibility via deep packet inspection (DPI) to detect, investigate, and respond to fraud before financial losses escalate.