Traditional antivirus software is supposed to have the resources to intercept any malicious action coming from a USB drive or other USB device. However, reality tells us that assumption is dangerously big. If your computer has to be exposed to USB drives that you don't directly control, you might want to add an extra layer of protection with the program Shiela USB Shield, which includes blocking autorun.inf and freezing any suspicious executable.
The Risks of Infected USB Drives
Even the strictest "air gaps" can fall on their knees before an infected USB drive. All it takes is a moment of carelessness, a "gifted" drive, or simply a lack of information. The biggest names in the malware world are ready to spread their code via USB, and we shouldn't forget BadUSB, which represents a tangible threat beyond its complex implementation. Every user knows how far they need to defend their systems. On more than one occasion I've said that paranoia works; however, attitude is only one component, and it must be accompanied by the right tools.
What Shiela USB Shield Does
That's how we get to Shiela USB Shield, a small application whose role is to block any potential threat coming from a USB drive, external hard drive, memory card, or similar storage device. Shiela USB Shield sits in the background like an antivirus, but its operation doesn't depend on a database; instead, it monitors the content on the drive. The first action is to intercept the execution of the infamous autorun.inf file, and then we have the automatic freezing of executables that might be infected. Shiela USB Shield can also change file attributes to reveal hidden content, or apply a certain immunization process, though its developer gives no details on that.
Requirements and Final Thoughts
Shiela USB Shield has relatively low requirements, but its main software dependency is version 2.0 of the .NET Framework, so that must be present on the system. Another detail to keep in mind is that the program must be run with elevated administrator privileges. Finally, Shiela USB Shield does not replace conventional antivirus. In fact, the program offers an option to invoke the installed antivirus, in case the user decides to perform a deeper scan. The software is free and completely open source.
