Hacked Custom PCs and Other Ways | Free Antivirus

 

The aforementioned methods are becoming less and less effective, and now the most widespread distribution of spam is via infected user computers. To gain access to a computer, scammers use Trojans (they spread over the Internet or file-sharing networks along with various pirated software), vulnerabilities in operating systems and popular software, and e-mail worms.

Anti-spam and Phishing Methods

As spam becomes more sophisticated, new ways of protecting mail are being developed and "classic" methods are becoming more sophisticated. The reliability of antispam systems is ensured by the use of several methods in combination. When choosing protection methods, it is also important to build on the specifics of the organization's work and the nature of the spam that comes in most often.

Filtration

The main and most popular method of fighting unwanted mail is filtering, that is, filtering out spam from really important messages. This method is based on the fact that spam emails differ significantly from regular emails. Filtration is divided into automatic and non-automatic.

Automatic spam filtering. Spam filters are used to protect against spam. They can be installed on user computers or servers. There are two fundamental differences between these filters. In one case, the spam filter recognizes the sender of an email as a spammer without opening the email itself based on the rating of the server through which the spammer sends emails. The peculiarity of this method is that the software must be installed on the server that receives unwanted mail.

Bayesian spam filtering is very popular at the moment. The method is as follows: spam filters are preliminarily "trained", that is, they are sent already sorted letters, on the basis of which the filter analyzes the statistical features of desired and unwanted correspondence. If "learning" is going well, then the filter helps filter out up to 97% of spam. Unfortunately, spammers have now learned to bypass such filters by inserting a picture into the "body" of the message, while removing the text in whole or in part. In this case, the spam filter cannot correctly identify the message and compile statistics. However, there is an antidote for such emails: if you constantly "train" antispam and point out its drawbacks, then automatic filtering becomes very effective.

Non-automatic filtration is more time consuming and difficult to adjust. But ultimately, if you approach the issue correctly, it can be very effective. For non-automatic filtering, spam filters are set by the user and, as a rule, consist of stop words or expressions. Therefore, the user will know exactly why the messages were filtered out and which ones were sent to the "Spam" folder. It is important to remember that for this anti-spam check to be effective, you need to constantly monitor the latest trends in spammer behavior and update the filter with new settings

Open Services (Open Relay, Open Proxy)

There are mail servers that allow any sender to send any message to any email address - they are called "open relays". It all started back in the mid-90s when absolutely all mail servers were just open relays (subsequently, the configurations of the world's major mail servers were changed). However, you need to make sure that the server is closed all the time, and IT security specialists do not always pay due attention to this, which is actively used by the search services for open relays or open proxy servers created by Internet scammers. Nevertheless, most spammers stopped using open relays, realizing their low effectiveness, and began to look for other methods of influence.