tailieunhanh - hack proofing linux a Guide to Open Source Security phần 4

Kiểm tra ghi khởi động của hệ thống. Tìm kiếm thư mục và thư mục con. Tự động xóa các tập tin bị nhiễm bệnh. Lưu quét vào một tập tin đăng nhập. Sử dụng một lên lịch nội bộ, hoặc lên lịch và bên ngoài, chẳng hạn như tại hoặc cron. Quét NFS gắn trên ổ đĩa. Xóa file bị nhiễm. Di chuyển các tập tin bị nhiễm một khu vực trung tâm "kiểm dịch" lựa chọn của riêng bạn. | 182 Chapter 3 System Scanning and Probing Figure Configuring the Nessus Client for a Detached Scan Security Alert __ Improper use of detached and differential scans can seriously impact host and network performance. Be very careful when configuring these options or you may inadvertently conduct a DoS attack against your own network. Exercise Conducting Detached and Differential Scans with Nessus 1. Make sure that the sendmail daemon is started etc sendmail start System Scanning and Probing Chapter 3 183 2. Make sure that sendmail is in your path. If you are using the BASH shell issue the following command echo PATH lots of output usr sbin Another way to do this is to just type which sendmail and examine the full path to the executable. That path should be in the output of the echo PATH command. 3. If sendmail is not in your path enter the following PATH PATH usr sbin 4. Now open your Linux nessus client. 5. Log in to your nessus daemon. Note__ Make sure the nessus daemon is compiled to allow detached scans. Use the usr local sbin nessusd-d command to learn more about the daemon s configuration. 6. In the Linux Nessus client select the plug-ins that you want to use. Configure any plug-ins as necessary. 7. Click on the Scan options tab and select both the Optimize the test and Detached scan will have to acknowledge that these scans can be dangerous. 8. Enter an e-mail address you can readily check in the Send results to this email address section. 9. When you have verified all settings click Start The Scan. After some time you will receive an e-mail report concerning the scan. If you receive no e-mail report then the scan did not find any vulnerabilities. 10. Now you are ready to do a differential scan. First conduct a full scan of a host. 184 Chapter 3 System Scanning and Probing 11. .