Daniel Zinanti, Information Security Analyst, TraceSecurity
In this digital age, data is not just valuable, it is currency. For financial institutions, protecting that data is very important. While many organizations invest heavily in firewalls, antivirus tools, and encrypted communications, one often-overlooked vulnerability still lurks in plain sight: removable storage devices, particularly USB drives.
Removable storage devices are incredibly convenient. They make data transfer fast, offline access possible, and backups simple. But that convenience comes with a dangerous tradeoff: they are a prime vector for cyberattacks, both accidental and deliberate.
Imagine this: a well-meaning employee plugs in a flash drive they purchased online to quickly move a presentation. Unbeknownst to them, that tiny device contains pre-installed malware, or worse, a keylogger, a hidden program that silently records every keystroke they make. Now the attacker has access to login credentials, financial records, client information, and potentially the keys to your institution’s internal systems.
This is not hypothetical. It is happening right now.
In 2022, the cybercriminal group FIN7 conducted a campaign targeting U.S. financial institutions and insurance companies by mailing malicious USB drives disguised as promotional gifts or legitimate devices. Some were labeled “Best Buy gift cards”; others looked like harmless company swag. The moment they were plugged in, malware was automatically installed, opening a backdoor for attackers to exfiltrate sensitive data and escalate privileges.
The sophistication of this attack proved one thing clearly: attackers know removable storage is a weak spot.
For financial institutions, the stakes are higher than in almost any other industry. Sensitive data includes: client personally identifiable information (PII), account numbers, login credentials, internal operational data, and regulatory and audit-sensitive documentation. A single infected device can lead to data breaches, regulatory fines, reputation damage, and loss of client trust. According to IBM’s 2023 Cost of a Data Breach Report, the average cost of a data breach in the financial sector was $5.9 million, with a significant portion stemming from insider threats and endpoint vulnerabilities like USB ports.
The first line of defense is restricting who can use removable storage and how.
If employees do not need USB access, disable the ports at the BIOS level or through group policy in Windows. For shared-use computers (like those in branches), disable all external media ports by default.
Human error is the weakest link. Run mandatory security training on the dangers of using personal or unknown USB devices. Encourage a “trust nothing, verify everything” mentality.
Tip: Add a visual element to training by showing how easy it is to load a malicious script onto a USB stick using tools like rubber ducky or bash bunny. A short demo goes a long way.
If a USB device must be used (such as for vendor transfers), require it to be first plugged into a quarantined machine that’s isolated from your internal network. Perform a full scan before allowing any file transfer.
Use logging tools and SIEM systems to monitor:
Integrating these alerts with your security incident response can help you catch threats early.
Prevention is much cheaper than recovery USB drives seem harmless; people see them as just another tool in the office drawer. But for a financial institution, one compromised drive can open the door to millions in losses, regulatory scrutiny, and irreparable brand damage. The good news? This is one of the most preventable attack vectors out there. Lock down your ports, lock down your policy, and stay ahead of the threat. Your data and your clients all depend on it!
Connect with TraceSecurity to learn more.