The paper "Principles of Сomputer System Design: Security" is a wonderful example of a book report on design and technology. The Thompsons rigged compiler is a deadly attack that is almost impossible to detect. However, its detection via login with the backdoor password proves an opportunity to resolve the issue using a technique known as diverse double compiling ( Saltzer & Kaashoek, 2009). Since it is not possible for Unix developers to inspect code in a production environment, inspecting the compiler code for the login program will not resolve the issue since the back door will continue appearing in future codes that the infected computer generates.
Consequently compiling the code using a trusted compile is key to overcoming the Thompson rigged compiler attacks. Using a different compile is a sure way of increasing diversity and reducing the limit of the attack. Whereas the Trojan may have affected the new compiler, in the same way, it is very unlikely that both compilers will have the same infection— Thompson rigged compiler. A developer can create a new compiler in a different UNIX machine and even impose more restrictions on the compiler regarding the output of the code.
The new compiler must have stringent rules and the developer must test this compiler to verify its integrity. The new compile will help compile the login program for use in the infected UNIX system. This technique makes it possible to prevent the recurrence of the Thompsons rigged compiler by using a trusted compiler. C-4.8 Malware such as Key loggers are difficult to evade, but using simple tricks and ways of obfuscating passwords are plausible intervention to the security problem Key loggers pose (Gawrock and International Conference Future of Trust in Computing, 2008).
As the scenario depicts, the key logger cannot capture any username and password from what the user will enter because it does not rely on screen and mouse capture. Entering the user name and password into the online bank account portal is possible using two screens (browser window and a text editing window open at the same time) along with a simple trick to obfuscate the passwords. First, the user will have to enter the username in the text editing software but include other dummy characters as part of the username.
For instance, if the username is thamer, the user can write tyt78h99adtmrteuir (notice the word in italics and bold representing the username). Once the user has written this string of characters, the user can select the dummy character (non-italics or bold) using the mouse and delete them using the right-click option accessed via right-clicking on the selection. Entering the password to the password text box window will only be through dragging and dropping the username— them. The user must repeat the same procedure for the password and remember to use the dummy data as in the first case and then dropping the password in its textbox.
The key logger will not detect the scheme, but the user will access the bank system securely. C-5.10 Network computers can come under threat from SYN flood that maximizes on the vulnerability of SYN cookie. In a networked environment, users can exploit the vulnerability of a computer system to execute a SYN flood that will devour system resources on the target server by using all the possible TCP connections available.