Application+Layer+Risks+and+Prevention

=** Application Layer Attacks **=

The seventh layer of the OSI model, also known as the application layer contains a wide variety of attacks. Attacks that are done at the seventh layer of the OSI model come in three categories:


 * **Programming Bug Exploits:** The process of developing applications is a long and rigorous process; as a result programming bugs occur once the application is made available for public use. Some of the bugs in applications will cause a security hole in a network so that an intruder can gain unauthorized entry into a network. An example of a programming bug exploit is a SQL injection attack which allows an intruder to run SQL commands in an input field.


 * **Phishing:** This form of an application layer attack is where an intruder will target a person and convince them that the application they are using is legitimate. As a result, people will submit personal information to thinking their information is safe. The attack is completely dependent on the person using the application.


 * **Resource exhaustion:** Similar to the transport layer Denial of Service attacks; resource exhaustion on the application layer has the same goal as it did on the transport layer, which is to crash the targeted machine. Instead of using the TCP protocol like before, resource exhaustion is done with an application that accepts a lot of data at once.


 * Application Layer Defense **

Due to the ever increasing types of application layer attacks and the constant name changes that they undergo, it is very difficult to list all of the known application layer attacks. Network Administrators should look into Intrusion Detection System (IDS) software. One type (and also free) IDS software is called Snort. Originally built for the Linux operating system, Snort is capable of detecting active and passive port scans, SMB probes, web application attacks and stealth scans. As it stands today, Snort is available for both Windows and Linux, keep in mind that there is slight learning curve when configuring Snort.