US Patent 10169586 Ransomware detection and damage mitigation

Systems and methods for file encrypting malware detection are provided. According to one embodiment, a monitoring module is installed within active processes running on a computer system by a kernel mode driver. Performance of a directory traversal operation on a directory of the computer system is detected by a monitoring module of a first process of the multiple active processes in which a parameter of the traversal operation includes a wildcard character. When a number of wildcard-based directory traversal operations performed by the first process exceeds a threshold, a decoy file is deployed by the monitoring module within the directory and the driver is notified. The driver monitors for and detects an attempt by the first process to tamper with the decoy file by intercepting and evaluating file system operations. Responsive to detection of the attempt, the first process is confirmed to be a malware process and is terminated.