Abstract: The present application discloses a method, system, and computer system for detecting malicious .NET files. The method includes receiving a sample that comprises a .NET file, obtaining information pertaining to common language runtime (CLR) metadata and streams associated with the .NET file, and determining whether the sample is malware based at least in part on (i) a classifier, and (ii) the information pertaining to the CLR metadata and streams.

Abstract: The present application discloses a method, system, and computer system for detecting malicious files. The method includes receiving a sample that comprises a .NET file, obtaining imported API function names based at least in part on a .NET header of the .NET file, determining a hash of a list of unmanaged imported API function names, and determining whether the sample is malware based at least in part on the hash of the list of unmanaged imported API function names.

Abstract: The present application discloses a method, system, and computer system for detecting malicious files. The method includes receiving a sample, extracting an embedded script from the sample, applying a malicious script detector in connection with determining whether the sample is malicious, and in response to determining that the sample is malicious sending, to a security entity, an indication that the sample is malicious.