Granted Patent B2

US 7,996,903 · App. 11/482,903 · Granted Aug 9, 2011

Assignee: Webroot Software, Inc.

Abstract

Claims (25)

1. A method for detecting and removing a hidden pestware file on a storage device of a computer, the method comprising:

detecting, using direct drive access, a file on the storage device, the direct drive access bypassing standard file Application-Program-Interface (API) function calls of an operating system of the computer;

determining whether the file is detectable by the operating system by attempting to access the file using a standard file API function call of the operating system, the file being detectable by the operating system when the attempt to access the file using the standard file API function call is successful, the file being undetectable by the operating system when the attempt to access the file using the standard file API function call is unsuccessful;

identifying the file as a potential hidden pestware file, when the file is undetectable by the operating system;

confirming through an automated pestware-signature scan of the potential hidden pestware file that the potential hidden pestware file is a hidden pestware file; and

removing automatically, using direct drive access, the hidden pestware file from the storage device;

wherein a backup copy of the hidden pestware file is made before the hidden pestware file is automatically removed from its original location on the storage device, the hidden pestware file thereby being quarantined to enable automatic recovery of the hidden pestware file when removal of the hidden pestware file is in error.

2. The method of claim 1 , wherein the standard file API function call of the operating system is GetFileAttributes.

3. The method of claim 1 , wherein the method is performed in conjunction with scanning a data-bearing portion of the storage device, the scanning being performed sequentially in sector order using direct drive access.

4. A system for detecting and removing a hidden pestware file on a storage device of a computer, the system comprising:

a file-detection module configured to detect, using direct drive access, a file on the storage device, the direct drive access bypassing standard file Application-Program-Interface (API) function calls of an operating system of the computer;

a file-analysis module configured to determine whether the file is detectable by the operating system by attempting to access the file using a standard file API function call of the operating system, the file being detectable by the operating system when the attempt to access the file using the standard file API function call is successful, the file being undetectable by the operating system when the attempt to access the file using the standard file API function call is unsuccessful;

a file-classification module configured to flag the file as a potential hidden pestware file, when the file is undetectable by the operating system;

a pestware-scanning module configured to confirm, through an automated pestware-signature scan of the potential hidden pestware file, that the potential hidden pestware file is a hidden pestware file; and

a pestware-removal module configured to remove automatically, using direct drive access, the hidden pestware file from the storage device;

wherein the pestware-removal module is configured to make a backup copy of the hidden pestware file before automatically removing the hidden pestware file from its original location on the storage device, the hidden pestware file thereby being quarantined to enable automatic recovery of the hidden pestware file when removal of the hidden pestware file is in error.

5. The system of claim 4 , wherein the standard file API function call of the operating system is GetFileAttributes.

6. The system of claim 4 , wherein the file-detection module is configured to scan a data-bearing portion of the storage device sequentially in sector order using direct drive access.

7. A computer-readable storage medium containing program instructions executable by a processor to detect and remove a hidden pestware file on a storage device of a computer, the program instructions comprising:

a first instruction segment configured to detect, using direct drive access, a file on the storage device, the direct drive access bypassing standard file Application-Program-Interface (API) function calls of an operating system of the computer;

a second instruction segment configured to determine whether the file is detectable by the operating system by attempting to access the file using a standard file API function call of the operating system, the file being detectable by the operating system when the attempt to access the file using the standard file API function call is successful, the file being undetectable by the operating system when the attempt to access the file using the standard file API function call is unsuccessful;

a third instruction segment configured to flag the file as a potential hidden pestware file, when the file is undetectable by the operating system;

a fourth instruction segment configured to confirm, through an automated pestware-signature scan of the potential hidden pestware file, that the potential hidden pestware file is a hidden pestware file; and

a fifth instruction segment configured to remove automatically, using direct drive access, the hidden pestware file from the storage device;

wherein the fifth instruction segment is configured to make a backup copy of the hidden pestware file before automatically removing the hidden pestware file from its original location on the storage device, the hidden pestware file thereby being quarantined to enable automatic recovery of the hidden pestware file when removal of the hidden pestware file is in error.

Assignments (9)

Continuity (1)