Receiving spam emails on SendMail

[Lauren Ambrose]

Hi,
For last couple of days I had found that there are tons of spam mails entering in my PC. Although I had not applied to any newsletter or subscription service for the same. I think the issue lies in the settings of email account where the spammers are retrieving my email id and sending spam messages to my account. What are the recommend settings for this.

[Jackson2]

Sendmail has been one of the most buggy software and has often been used to compromise systems. The first rule of safety with Sendmail is to always use the latest version, this is also true of any way to other servers. The second is the infamous hacking / etc / sendmail.cf: If you only use Sendmail to send mail without going through the gateway of your ISP, then add O DaemonPortOptions = Addr = 127.0.0.1'. Thus, Sendmail will relate only to the loopback interface, and it will therefore not see the Internet! (netstat display 127 .0.0.1: smtp 'and not' : smtp '). You can also put the IP of your ethernet interface instead of 127.0.0.1 but this time you can not send mail locally but other machines on your network can use your Sendmail without Internet hackers can not see.

[Techno01]

You must set the IP addresses that can use sendmail in / etc / mail / ip_allow. If your Sendmail must be viewed from any interface and you're not afraid to load your CPU, you can run under inetd (with sendmail-bs), so use ACLs TCPWrappers. In this case, periodically run sendmail-q30m to clear the queue. Add O = PrivacyOptions goaway to disable the SMTP VRFY command which can be used to discover information about user accounts on your server.

[Trio]

Here's a little trick to solve a common problem if you use Netscape Communicator to surf and send email: Your email will be used for both FTP and email. Therefore, anyone on the Web can retrieve your email address. For this they put a bogus link in ftp on their webpage. When viewing the page, Communicator connects to the ftp site (to retrieve an image for example) and your email is logged by the FTP server, ready to be distributed by spammers.

[deveritt]

If you wan to avoide set up an email address masquerading then you can use linuxconf or tweak sendmail.cf. For this the # Masquerading rules is S1 / Rwar <@ mail.net> $ @ me <@ mail.net> and Rwar <@ mail.net.> $ @ Me <@ mail.net. This setting must be configured properly in your sendmail file so that your email must not retrieved on internet.

[Techguru01]

Only configuring the sendmail.cf files will not do. You have to initialize your email in Communicator which is abc@mail.net. If you connect to an ftp site, you send abc@mail.net and your real email will not be revealed. But if you send mail, Sendmail will replace 'abc@mail.net' with your actual email xx@mail.net. And on arrival, all you notice, it will be much less spam in your mail.