To hide a file behind a image file which means that if any one opens that image he will see the image only but if you open in a special way then you can open the hidden file behind the image.
Passwords are Stored and Transmitted in an encrypted form called a Hash. When a User logs on to a system and enters a password, a hash is generated and compared to a stored hash. If the entered and the stored hashes match, the user is authenticated (This is called the Challenge/Response).
Keystroke Loggers (or Key loggers) intercept the Target’s keystrokes and either saves them in a file to be read later, or transmit them to a predetermined destination accessible to the Hacker.
Since Keystroke logging programs record every keystroke typed in via the keyboard, they can capture a wide variety of confidential information, including passwords, credit card numbers, and private Email correspondence, names, addresses, and phone numbers.
The act of sending an Email to a user falsely claiming to be an established legitimate enterprise in an attempt to scam the user into surrendering private information that will be used for identity theft.
Email Spamming is a variant of Bombing; it refers to sending Email to hundreds or thousands of users (or to lists that expand to that many users). Email spamming can be made worse if recipients reply to the Email, causing all the original addressees to receive the reply. It may also occur innocently, as a result of sending a message to mailing lists and not realizing that the list explodes to thousands of users, or as a result of a responder message (such as vacation(1)) that is setup incorrectly.
Email spoofing is the forgery of an Email header so that the message appears to have originated from someone or somewhere other than the actual source. Distributors of spam often use spoofing in an attempt to get recipients to open, and possibly even respond to, their solicitations. Spoofing can be used legitimately.
SMTP stands for Simple Mail Transfer Protocol. SMTP is used when Email is delivered from an Email client, such as Outlook Express, to an Email server or when Email is delivered from one Email server to another. SMTP uses port 25.
Email sending and receiving is controlled by the Email servers. All Email service providers configure Email Server before anyone can Sign into his or her account and start communicating digitally.
Once the servers are ready to go, users from across the world register in to these Email servers and setup an Email account. When they have a fully working Email account, they sign into their accounts and start connecting to other users using the Email services.
Every Ethical Hacker must follow few basic principles. If he do not follow, bad things can happen. Most of the time these principles get ignored or forgotten when planning or executing ethical hacking tests. The results are even very dangerous.
What can be done to prevent Hackers from finding new holes in software and exploiting them?
Information security research teams exist—to try to find these holes and notify vendors before they are exploited. There is a beneficial competition occurring between the Hackers securing systems and the Hackers breaking into those systems. This competition provides us with better and stronger security, as well as more complex and sophisticated attack techniques.
The main reason why Hackers hack is because they can hack. Hacking is a casual hobby for some Hackers — they just hack to see what they can hack and what they can’t hack, usually by testing their own systems. Many Hackers are the guys who get kicked out of corporate and government IT and security organizations. They try to bring down the status of the organization by attacking or stealing information.
The Art of exploring various security breaches is termed as Hacking.
Computer Hackers have been around for so many years. Since the Internet became widely used in the World, We have started to hear more and more about hacking. Only a few Hackers, such as Kevin Mitnick, are well known.