Organizations use local area networks and wide area networks to communicate with multiple mail servers as well as Web servers. Network hackers are always on the prowl to attack an organization's network. Although these attacks mostly take place at major financial institutions, government agencies and pharmaceutical companies, that does not mean that an organization that deals in any other business is free from the network hacker. A patient network hacker would not compromise the network servers during normal working hours. He will usually launch an attack between 9 p.m. and 6 a.m., reducing the likelihood of anyone knowing about the attack. This gives the network hacker more time to apply sniffers and backdoors on the network hosts without having to worry about the presence of system administrators. Here are some areas that are mostly targeted by hackers:
- A hacker can apply social engineering to gain confidential information from companies by pretending to be an employee and calling other employees to gain useful information.
- Mail Servers are common targets when hackers want to gain access to network resources. Companies that access e-mail from the Internet, especially, are potential targets. To prevent a mail server from being attacked, ensure that the latest security patch is applied to both the operating system and the e-mail application.
- Network hackers scan for vulnerabilities in a firewall that is not configured properly
- or does not have proper configuration updates. A properly configured firewall is one measure that can prevent a hacker from attacking a network.
- Filtering routers are also another main source targeted by hackers with aggressive SNMP scanners. If an attack is effective, the router can easily be turned into a bridge, thus allowing unauthorized access to the network.
- Network hackers can also intercept data transmitted over the network to mail servers. Network administrators can prevent this from occurring by using 128-bit key encryption when transferring information over the Internet or to mail servers.
About the author
Adesh Rampat has 10 years' experience with network and IT administration. He is a member of the Association of Internet Professionals, the Institute for Network Professionals and the International Webmasters Association. He has also lectured extensively on a variety of topics.
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Internet and E-mail Security Kit : Defeat Hackers and Viruses and Increase Network Security
Author : Syngress Publishing
Publisher : Syngress, Media
ISBN/CODE : 1928994288
Cover Type : Soft Cover
Pages : 1376
Published : March 2001
This was first published in May 2001