Abstract: Disclosed herein are systems and methods for granting access to a file. In one aspect, an exemplary method comprises, calculating a first hash of a portion of the file, searching for the first hash in a local database, when the first hash is found indicates that the file is malicious, calculating a second hash, searching for the second hash in the verdict cache, and pronouncing a final decision as to a harmfulness of the file, and when either the first hash is not found in the verdict cache or the first hash is found and indicates that the file is trusted, granting access to the file, calculating a second hash of the file, generating a request for information about the file and sending the request to a remote server, and pronouncing a decision as to harmfulness of the file based on results of the search received from the remote server.

Abstract: Disclosed herein are systems and methods for granting access to a file. In one aspect, an exemplary method comprises, calculating a first hash of a portion of the file, searching for the first hash in a local database, when the first hash is found indicates that the file is malicious, calculating a second hash, searching for the second hash in the verdict cache, and pronouncing a final decision as to a harmfulness of the file, and when either the first hash is not found in the verdict cache or the first hash is found and indicates that the file is trusted, granting access to the file, calculating a second hash of the file, generating a request for information about the file and sending the request to a remote server, and pronouncing a decision as to harmfulness of the file based on results of the search received from the remote server.

Abstract: Disclosed herein are systems and methods for generating a request for information on a file to perform an antivirus scan. In one aspect, an exemplary method comprises, intercepting the file, synchronously calculating a first hash of a portion of the file, searching in a verdict cache, when the hash is found, determining whether the hash belongs to a list of malicious files, when it belongs to the list of malicious files, synchronously calculating a second hash, searching for the second hash in the verdict cache, and pronouncing a final decision as to harmfulness of the file, when the first hash does not belong to the list of malicious files, granting access to the file, asynchronously generating a request for information about the file, calculating a second hash, searching for the information in a verdict cache, and pronouncing a decision as to harmfulness of the file.

Abstract: Disclosed herein are systems and methods for generating a request for information on a file to perform an antivirus scan. In one aspect, an exemplary method comprises, intercepting the file, synchronously calculating a first hash of a portion of the file, searching in a verdict cache, when the hash is found, determining whether the hash belongs to a list of malicious files, when it belongs to the list of malicious files, synchronously calculating a second hash, searching for the second hash in the verdict cache, and pronouncing a final decision as to harmfulness of the file, when the first hash does not belong to the list of malicious files, granting access to the file, asynchronously generating a request for information about the file, calculating a second hash, searching for the information in a verdict cache, and pronouncing a decision as to harmfulness of the file.