Spam folder in the mail client Mail: E-mail The largest flow of spam is distributed via electronic mail (e-mail). Currently, the proportion of viruses and spam in general traffic, e-mail is on an estimated 70 to 95 percent . As spam is most frequent advertising unpopular products: rolex, viagra, etc. . Spammers collect e-mail addresses by using a special robot, or manually (rarely), using a web page, conference Usenet, mailing lists, electronic bulletin boards, guest books, chat rooms … This robot software is able to collect thousands of addresses per hour and create one database for further distribution by them as spam. Some companies only deal with the collection of addresses, a database and then sell. Some companies sell spammers e-mail addresses of their customers, they
have ordered goods or services via e-mail. There is another way to get a long list of e-mail addresses: the addresses are generated by first randomly on specified patterns (from thousands to a million), and then just checked the special program-validator on their validity (existence). To send spam is used connected to the Internet not protected or properly configured computers. These may include: Servers that are in error are such that allow free mail forwarding (open relay, open proxy). Webmail services that allow anonymous access, or access to a simple registration of new users (who can perform special robot software). Computer-zombies.
Some spammers are using known vulnerabilities in software or computer viruses in order to capture the management of a large number of computers connected to the Internet, and use them to send spam. Mail servers that send Bounce-message when it is not possible to deliver a letter. Spammers send a letter to the obviously non-existent address, indicating a forged sender address (the one on which you want to get spam). The server creates an email with the error message and sends it to the specified address, often placing it and the text of the original letter. It should be noted that such behavior is the server with the standards adopted by the Internet, in fact, in some cases, it is the only way to notify the sender of the problem (for example, when sending messages through several consecutive servers), however, the guide for system administrators often makes recommendations to configure mail server in such a way that when you try to deliver a letter to an unused address of the server instead of creating an error message would have tore the compound.
Use different kinds of vulnerabilities and not obvious wrong (or conservative) setting mail servers for unauthorized distribution SPAM. For the difficulty of automatic filtering of spam messages are often distorted – the letters are used instead of similar style numbers, letters – instead of the Russians, in random places added gaps. We use other techniques. There are various tricks to make sure that the message received and read. Among them: Request for confirmation of delivery. Some mail clients can send it automatically. Letters that contain images that are downloaded from sites controlled by spammers. Links to web pages that are invited to learn more. Proposal to unsubscribe to this mailing list by sending a letter to the specified address (in fact, delivery is usually not terminated). If spammers get confirmation that the email address actually being used, then the flow of spam could be increased many times over. Usenet Many newsgroups Usenet, especially nemoderiruemye were abandoned by users, and now contains almost exclusively advertising, often not even on topic. Instead, others were created moderated conference. Instant Messaging With the development of the delivery of instant messages, spammers have been using them for their purposes.
Many of these services provide a list of users that can be used to send spam. A narrower called this type of spam – sleep (SP am + I nstant M essenger). Blogs, wikis, forums, message boards In recent years become popular Web sites where you can leave comments (such as forums and blogs), or those that can be freely edited – wiki. As these pages open for the free editing, they can be posted Spam – splogi. Such spam is all the more irritating that its difficult to remove (as a rule, messages in the forums and blogs can edit only the privileged users – consequently, a private party should communicate with anyone of them). Another kind of spam in blogs is a universal, often – automatic, introducing users to the list of «friends», without getting acquainted with their personal pages, as a rule, in order to artificially raise their rank by obtaining «Mutual» friendship, or to draw attention to the online advertisements placed log spammer. This type of spam is sometimes referred to as «Frendospamom» (from the English. Friend – a friend).