1 00:00:02,270 --> 00:00:09,480 Another type of scanning that doesn't reveal her identity is passive scanning it exploits the fact that 2 00:00:10,290 --> 00:00:15,970 as we've mentioned before every TCAP IP stack implementation is a little different. 3 00:00:20,480 --> 00:00:24,080 The time to live attribute of the IP protocol is one example. 4 00:00:25,930 --> 00:00:35,240 Different operating systems set different initial values of this attribute windows said that 128 Linux 5 00:00:35,360 --> 00:00:43,170 64 we can check the value of the TTL attribute and learn something about the computer which sent the 6 00:00:43,170 --> 00:00:44,550 packet. 7 00:00:44,580 --> 00:00:48,150 This is true in regards to many other protocols and their attributes. 8 00:00:49,640 --> 00:00:56,650 By passive scanning it is merely listening to the data we are able to obtain crucial information about 9 00:00:56,650 --> 00:00:59,460 the targets operating system. 10 00:00:59,510 --> 00:01:01,890 This is how the lbf program works. 11 00:01:03,470 --> 00:01:05,720 Shortly we will see the program in action 12 00:01:13,350 --> 00:01:20,280 attackers always choose the easiest target to find the easiest target check whether somebody has made 13 00:01:20,280 --> 00:01:23,870 basic configuration mistakes. 14 00:01:23,990 --> 00:01:30,600 You can do that by vulnerability scanning tools such as Ness's scanner which are designed to perform 15 00:01:30,600 --> 00:01:38,100 security level analysis can be used also to check the system's vulnerability to attacks. 16 00:01:38,100 --> 00:01:44,380 The program includes a database of all known security bugs in various kinds of software. 17 00:01:44,510 --> 00:01:49,820 It can perform a remote computer scan looking for security gaps that would match any description in 18 00:01:49,820 --> 00:01:52,020 its database. 19 00:01:52,030 --> 00:01:57,400 This is used primarily to scan web servers because they are being accessed remotely via the Internet 20 00:01:57,490 --> 00:01:58,330 all the time.