fast spreading using wide network (internet), sometimes uncontrollable
Trojan Horse:
a software that hides inside another software, need user interaction to make it active. mostly give destructive impact!

Places that usually used by virus to defend itself:
Task Manager
Configuration Files (WIN.INI, SYSTEM.INI, MSConfig etc)
System Directories

Social Engineering:
Send a copy of “important” file using flash disk
Send an email with “important” attachment
Give link to the victim to redirect them to fake website

Share document as public when you are connected to the network is very dangerous. Other users can use port scanning software to detect open port from all users that connected to the same network. When the software detect a public shared folder, the user can easily have access to the folder. Firewall can be used to block every unauthorized access from our computer

DoS – Denial of Service – send large quantities of data packet to one destination, so the server will not be able to do other process.
DDoS – Distributed Denial of Service – form “troop” of computers (usually known as zombie server), planting backdoor in each zombie server, so when the user activate it, all the computers will attack at the same time to one target that has been identified. This requires time, to plant the backdoor, to prepare all the zombie servers and generate the code to activate it.

Computer forensics (sometimes known as computer forensic science) is a branch of digital forensic science pertaining to legal evidence found in computers and digital storage media. It’s often used by group of people to recover some deleted files to find the evidence for some criminals act.

MySQL Injection Attack can be avoided by always updating the version of the software and MySQL Database. It can also be avoided by using specific command in MySQL when passing the string parameters, such as mysql_real_escape_string() method. Installing a firewall software, SSL and Anti Virus would be also recommended in this case

Some methods of Computer Forensic:
Data Recovery
Some criminals often delete all the evidences from your computers. Person from Computer Forensic can try to recover it using some tools, such as Magic Uneraser or other similar programs
Tracing Cookies
Some people has lack knowledge about cookies. We can use these to track the recent website that has visited by criminals, even though they already removed the history
Reading the server logs
From the logs, we can see the activity of the criminal. What the recent program they use, how long they use the program etc.

SSL : Secured Socket Layer – established a secured communication between client and server, while all the transmitted data packet is encrypted.
Strengthen the security by upgrading the software used for running web application, updating the patch, always enable the firewall etc.
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