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Honest spam

Everyone knows that recently the Internet has become used, on the one hand, much simpler and more convenient – a lot of different services have appeared, the interfaces of sites are becoming more convenient and smarter, connections to the Network are faster and more reliable, and on the other – much more dangerous and more complicated the number of all kinds of worms, trojans, scanners and spam rolls over all imaginable limits. For example, an analysis of the logs on the serversoft.ru server showed that, with protection turned off for a day, about a thousand different worms would fall into my box, about the same number of letters from spammers and only 150–200 “normal” letters, including mailings.
Nowadays, a significant part of spam is made up of non-delivery messages of allegedly sent messages. Which is typical, in addition to all this good, more than a thousand messages about viruses found in my letters and about undelivered messages would have come. I think it is unnecessary to mention that I do not send any viruses or messages to strangers … What is happening?

And everything is simple. As you know, the SMTP protocol used for sending e-mail is very insecure and allows any user to specify any return address – even though Bill Gates, although Vasi Pupkin. And the recipient machine, if it suddenly finds some error in the letter, will honestly inform the person whom it considers the sender of the error that occurred. And the unfortunate Bill will be notified that his letter was not delivered to Vasya Pupkin for such and such a reason.

Notifications about viruses intercepted on the road, as a rule, do not get to those people who send these viruses! It is surprising that people who are well aware of this problem do not react to it at all. If you read the descriptions of various worms, then the antivirus companies honestly write that, they say, this harmful bad virus reads the address book of the infected machine and forges the return addresses. And these same antivirus companies release products that, upon receiving an infected email, send a message about the intercepted virus not only to the administrator of the receiving machine, but also to the sender! Which, as they themselves admit, is unsuspecting and has done nothing bad to anyone.

Mail system administrators must configure their systems in accordance with the requirements of the time. Although, to be more honest, it is not so much antivirus vendors who are responsible for this behavior of mail systems, as mail server administrators – after all, they are setting up the system! But for some reason they continue to use the settings of the last century – then spam and worms were still relatively rare, and notifying the sender about an error in the address or infection of his machine was a good tone …

Checking letters at the reception can make life much easier. Nowadays it will be much more correct to change the behavior of your mail system somewhat. The easiest way out is to simply kill such a letter when you receive a virus, without saying anything to anyone, or perhaps by informing the recipient system administrator. With a great desire, you can save the letter itself “for further study.” It is even better to check the name of the virus found, and if it contains the word “worm”, then kill the letter quietly, but if it is a “normal virus”, then inform the sender and the administrator. You can also check the presence of attachments with the vbs, pif, bat, com and similar extensions at the receiving letter stage and refuse to receive such a letter with the 5x code and a clear explanation that such attachments are not skipped.

Do not forget that worms send themselves on their own, and one infected computer in a corporate network can compromise the entire network. In addition, it will be very useful to enable anti-virus scanning of outgoing emails from “their” users (which is disabled by default on many servers) – this will help to warn them, if they somehow manage to infect their computer and become the carriers of the infection themselves …

It is also worth adjusting the behavior of your system when spam is detected (I think it’s not necessary to say that it is desirable to install some anti-spam program). The difficulty lies in the fact that spam detection is a probabilistic process, and most anti-spam programs can only classify email with more or less confidence as spam – which is why administrators often do not run the risk of automatically removing spam — after all, it is impossible to rule out the erroneous response of a filter, but for an undelivered message the user can be very offended …

Let users decide for themselves how much spam prevents them. But who prevents to implement the profile scheme that a user can choose? Let’s say that the most secure profile will add marks to the headers and subject of the message that the letter is rated as spam – this will allow the user to easily filter such letters and view them in their free time. A more aggressive filter will delete letters with a high probability of spam.

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