| 摘要 |
<p>PROBLEM TO BE SOLVED: To surely detect malware infection in a system by effectively analyzing a log for determining a Web site.SOLUTION: A list generation management device generates a white list with low malignancy, a black list with high malignancy, and a gray list not belonging to both of the white list and the black list, on the basis of malignancy of a Web site calculated from a log of a proxy server or the like. An additional authentication server requests additional authentication when connecting to the Web site included in the gray list, distributes the gray list to the white list when the additional authentication successes, and distributes the gray list to the black list when the additional authentication did not succeed even once for a certain period of time. The additional authentication is performed in a manner of image authentication that cannot be recognized by a person.</p> |
