Network based Security Attacks
Network is a collection of nodes connected to each other. These nodes can be a computer or computing devices (like mobile and PDA), peripheral devices (like printer, scanner), other networks (connect via bridge or router) or any service (like directory service, mailing service) etc. As the boom in networking has joined whole world in one network called the Internet, we have also joined with many new problems. These are due to malicious activity peoples who – intentionally or unintentionally and for profit or without profit trying to harm us. To be protected and to be secure it is necessary to understand their way of action. This small note will help you understand these attacks.
Types of Attack –
Network based security attacks can be categorized in following. This list is based on a server, a user accessing data on the server and data that the server holds.
1. Attack on availability – making any part or whole network unavailable to users. Distributed Denial of Service (DDOS) is one of the best examples of network attack. In this the server is clogged in such a way that the server starts denying services to legitimate users.
2. Attack on confidentiality – unauthorized access of any data. It can be active or passive. Eavesdropping is one of the best examples of such attack. In this network line is tapped or gained access.
3. Attack on Integrity – attack on confidentiality and then modifying any part or whole data. One of the famous attack in this category is changing the secure HTTP content by using some local proxy.
4. Attack on authenticity – creating data and sending it to users by faking themselves as authentic. Now days a very famous spamming technique called scams is cheating users world wide. In this a mail that is believed to be sent from any authorized bank is send. In the mail request of data is asked and a link that seems authentic in url text is given. The url can be like http://www.xyzbank.com/register/user.php but the url is something like [http://221.211.2.222/.http://www.xyzbank.com] which is incorrect. Many users are trapped by these scammers.
5. Attack on access control – faking as an authentic user and utilizing all resource provided to that user. It is very common sometimes active sometimes passive, many users try to enter server’s computer and also many of hackers gained access in computers from defense labs to PC’s. A fresh case of this is use of Robots. These are small programs which were entered in the victim computer. These programs are capable of taking commands from network and then executing them on the victim’s computer. A teenager group has caught, since they break up in a hospital’s ICU computers and damaged vital schedules of it.
6. Attack on privacy – Gaining access of user’s computer and spy on its usage and then selling this information to many business bodies, so that they can target their customers. It is now becoming one of the most common attacks. Spywares are installed on the victim’s computer and all surfing information is uploaded to some desired marketing site. This is later used as weapon of mass advertisement.
How to secure our data
There is no one panacea solution for this. Better practice of security can help. Some attacks can be reduced by using software and some by being careful.
Carefully handle your mail – whenever you get mail regarding - providing any vital information like account no. and password, don’t jump on any conclusion. Mail the responsible authority with a copy of that mail and get what you have to do. Check that the link given and the URL text written are same. If you find something fraudulent, immediately contact police or responsible certification authority.
When you are about to purchase something through Internet, make sure that the seller is certified by CA (certifying authority) like VeriSign or any other renowned CA of your country. Also read the certificate and check if the certificate is not invalid and is not invoked by the CA.
Software that can help you
Many free software and patches for vulnerability are available. The best to have is a good virus scanner like AVG free virus scanner, running on your computer in real time. You should also know that virus scanner work on the basis virus available at the moment, so any old virus scanner will not find newly created viruses. For this you must install the updates time to time.
Other than virus scanners, there are many other softwares working against network based security attacks. I will not give any name of software but I will give you types of software that can be used. You can search them at http://www.download.com.
Firewalls – there are many typed of firewalls that one can run, but we are concerned here about proxy based firewalls. Such a firewall setup a proxy server on your computer, this proxy scans all out going requests and incoming responses from your computer. This way they block any unauthorized access to your computer.
Spyware sweeper – Spywares can be small software installed on your computer or cookies based online spy of your system. A Spyware sweeper first searches all possible locations of Spywares like cookies, your system registry, start up folder of your Windows and system’s root. After finding that, they ask you what action they should take, like, deleting, shielding or blocking such Spywares. If you browse the Internet using low security software like Internet Explorer, this is highly recommended that you should use a Spyware sweeper.
Network block – even if your computer is secure and virus – Spyware free, other computer attached to your computer network can setup them. This can be cured by using network blockers. These are firewall software that runs in real time and alert you with all LAN based packets coming to your system. Such software provide you facility to unblock few parts of your network also.
Conclusion
Finally, I can say that never curse others who damaged your computer or information, curse yourself that you were not able to block them.
“If you actively not attack them, they will actively attack you.”
Be careful, be updated and know all moves of your opponents (malicious software) before they even have taken any step. If you want to be simple user of network based system, them you are candidate of being victim also. A smart move can thwart your opponents and help you stand unaffected in swamp of malicious software.
Manu Dutt Tripathi is a young energetic computer professional working as a consultant DBA in leading IT firm of Bangalore, India. He has a master degree in computer science. He is a active member of many technical forums and help users and computer professional through out the world.
More such ideas can be found at http://manudutt.wikispaces.com
