1) Inside Jobs - Most security breeches originate inside the network that is under attack. Inside jobs include stealing passwords (which hackers then use or sell), performing industrial espionage, causing harm (as disgruntled employees), or committing simple misuse. Sound policy enforcement and observant employees who guard their passwords and PCs can thwart many of these security breeches.
2) Rogue Access Points - Rogue access points (APs) are unsecured wireless access points that outsiders can easily breech. (Local hackers often advertise rogue APs to each other.) Rogue APs are most often connected by well-meaning but ignorant employees. .
3) Back Doors - Hackers can gain access to a network by exploiting back doors�'administrative shortcuts, configuration errors, easily deciphered passwords, and unsecured dial-ups. With the aid of computerized searchers (bots), hackers can probably find any weakness in your network. .
4) Viruses and Worms - Viruses and worms are self-replicating programs or code fragments that attach themselves to other programs (viruses) or machines (worms). Both viruses and worms attempt to shut down networks by flooding them with massive amounts of bogus traffic, usually through e-mail. .
5) Trojan Horses - Trojan horses, which are attached to other programs, are the leading cause of all break-ins. When a user downloads and activates a Trojan horse, the hacked software (SW) kicks off a virus, password gobbler, or remote-control SW that gives the hacker control of the PC. .
6) Denial of Service - DoS attacks give hackers a way to bring down a network without gaining internal access. DoS attacks work by flooding the access routers with bogus traffic (which can be e-mail or Transmission Control Protocol, TCP, packets). .
Distributed DoSs (DDoS5) are coordinated DoS attacks from multiple sources. A DDoS is more difficult to block because it uses multiple, changing, source IP addresses. .
7) Anarchists, Crackers, and Kiddies - Who are these people, and why are they attacking I your network? .
Anarchists are people who just like to break stuff. They usually exploit any target of opportunity. .
Crackers are hobbyists or professionals who break passwords and develop Trojan horses or other SW (called warez). They either use the SW themselves (for bragging rights) or sell it for profit. .
Script kiddies are hacker wannabes. They have no real hacker skills, so they buy or download warez, which they launch. .
Other attackers include disgruntled employees, terrorists, political operatives, or anyone else who feels slighted, exploited, ripped off, or unloved. .
8) Sniffing and Spoofing - Sniffing refers to the act of intercepting TCP packets. This interception can happen through simple eavesdropping or something more sinister.
Spoofing is the act of sending an illegitimate packet with an expected acknowledgment (ACK), which a hacker can guess, predict, or obtain by snooping. .
As the cost of hacking attacks continues to rise, businesses have been forced to increase spending on network security. However, hackers have also developed new skills that allow them to break into more complex systems. Hacking typically involves compromising the security of networks, breaking the security of application software, or creating malicious programs such as viruses. .
The most popular forms of network hacking are denial of service (DoS) attacks and mail bombs. DoS attacks are designed to swamp a computer network, causing it to crash. Mail bombs act in a similar fashion, but attack the network's mail servers. When eBay was attacked in February 2000, its Web server was bombarded with fake requests for Web pages, which overloaded the site and caused it to crash. Network hackers also try to break into secure areas to find sensitive data. Once a network is hacked, files can be removed, stolen, or erased. A group of teens in Wichita, Kansas, for example, hacked into AOL and stole credit card numbers that they then used to buy video games. .
Application hackers break security on application software-software including word processing and graphics programs-in order to get it for free. One way they gain access to software that requires a serial number for installation is by setting up a serial number generator that will try millions of different combinations until a match is found. Application hackers also sometimes attack the program itself in an attempt to remove certain security features. .
Hackers that create viruses, logic bombs, worms, and Trojan horses are involved in perhaps the most malicious hacking activities. A virus is a program that has the potential to attack and corrupt computer files by attaching itself to a file to replicate itself. It can also cause a computer to crash by utilizing all of the computer's resources. For example, e-mail systems were inundated with the "ILOVEYOU" and the "Love Bug" viruses in May of 2000, and the damage to individuals, businesses, and institutions was estimated at roughly $10 billion. Similar to viruses, logic bombs are designed to attack when triggered by a certain event like a change in date. Worms attack networks in order to replicate and spread. In July of 2001, a worm entitled "Code Red" began attacking Microsoft Internet Information Server (IIS) systems. The worm infected servers running Windows NT 4, Windows 2000, Windows XP, and IIS 4.0 and defaced Web sites, leaving the phrase "Welcome to www.worm.com Hacked by Chinese!" Finally, a Trojan horse is a program that appears to do one thing, but really does something else. While a computer system might recognize a Trojan horse as a safe program, upon execution, it can release a virus, worm, or logic bomb. .
