tailieunhanh - Practical UNIX & Internet Security phần 4

với một chương trình như người nhận, do đó cho phép người dùng từ xa để gọi vỏ và các chương trình khác trên các máy chủ đích. sendmail đã làm được một công việc người nghèo chứng thực đối số của nó, do đó cho phép người sử dụng ghi đè lên các vị trí tùy ý trong bộ nhớ, hoặc cung cấp đầu vào mà kết quả trong các tác dụng phụ rất xấu. | Chapter 12 Protecting Computer Hardware Remember high-density RAM modules and processor cards are worth substantially more than their weight SimpoP DRMergecandpSplit UtnregisteredVersions - http than it did the day before check its RAM and then check to see that its case is physically secured. Physically secure your computer A variety of physical tie-down devices are available to bolt computers to tables or cabinets. Although they cannot prevent theft they can make theft more difficult. Encryption If your computer is stolen the information it contains will be at the mercy of the equipment s new owners. They may erase it. Alternatively they may read it. Sensitive information can be sold used for blackmail or used to compromise other computer systems. You can never make something impossible to steal. But you can make stolen information virtually useless - provided that it is encrypted and that the thief does not know the encryption key. For this reason even with the best computer-security mechanisms and physical deterrents sensitive information should be encrypted using an encryption system that is difficult to break. 5 We recommend that you acquire and use a strong encryption system so that even if your computer is stolen the sensitive information it contains will not be compromised. 5 The UNIX crypt encryption program described in Chapter 6 Cryptography is trivial to break. Do not use it for information that is the least bit sensitive. Portables Portable computers present a special hazard. They are easily stolen difficult to tie down they then cease to be portable and often quite easily resold. Personnel with laptops should be trained to be especially vigilant in protecting their computers. In particular theft of laptops in airports is a major problem. Note that theft of laptops may not be motivated by greed resale potential alone. Often competitive intelligence is more easily obtained by stealing a laptop with .