Program Threats in Operating System:
Definition and Explanation:
Often one user writes a program to be used by another user. In these cases, misuse can occur and lead to unexpected behavior. The two most common methods by which such behavior may occur are Trojan horses and trap doors.
1. Trojan Horse:
One of the most serious threats to computer security is Trojan horse attack. A Trojan horse is a malicious, security-breaking program that is disguised as something harmless such as a screen saver or game. A famous Trojan horse was the so-called "Love Bug".
When programs are written by users to be executed by other users, the user can misuse the rights of the program if they execute the program in a domain that provides the access rights of the executing user.
One can end such program by ending the interactive session with a sequence of key pressing such as control-alt-delete combination in Windows 95/98/NT systems.
2. Trap Doors:
When a programmer leaves a hole in the software, only he is capable of gaining access to it A trap door is basically a program where the programmer might illegally or legally Write the code to avoid normal security procedures for specific user.
Trap doors are difficult problems to detect because they are in the source code where software systems can contain millions of lines of code.