Sharing files via USB drives or external hard drives introduces security and operational risks compared to networked sharing methods. Primarily, these portable devices can unknowingly carry malware like viruses, ransomware, or spyware from one computer to another, bypassing network security defenses. Plugging an infected drive directly into a system can allow malicious software to install and spread stealthily. Furthermore, these small physical devices are easily lost or stolen, leading to potential unauthorized access to sensitive files if the data isn't encrypted. They can also introduce compatibility issues between different operating systems.

Practical examples highlight these risks. In corporate settings, an employee might accidentally introduce malware via an infected USB drive downloaded from home, compromising the entire internal network. A lost external drive containing unencrypted customer data, patient records, or critical financial documents could lead to a significant data breach and regulatory fines. Students or freelancers often use USB drives for transferring work; losing one containing academic research or client files represents a direct loss of critical information and effort.

The major advantage of USB drives—their portability and offline use—is also their key vulnerability, creating significant data loss and exposure risks. Robust mitigation includes enforcing policies against untrusted USB use, requiring encryption for all data on portable drives, employing strict access controls, and relying on secure cloud sharing where possible. While convenient for temporary transfers offline, the prevalence of threats necessitates careful management and alternative solutions for sensitive data sharing, especially considering their vulnerability to physical damage over time.