Sendmail and user accounts

[Gaddis, Jeremy L.]

On Wed, 7 Feb 2007, Rushan Sobar wrote:
> I'm running a fedora core 4 box and recently I notice spam and junk e-mails passing to user's that not shown to public and hard name user's that hard to be guess by dictionary or e-mail generator, I would like to ask is there any way that some can figure or scan for active user names on my box , is there anything that I should check to be sure than no one can extract active username of e-mails?

vi sendmail.cf, find the line that says "PrivacyOptions" and change it to
"O PrivacyOptions=novrfy,noexpn", if you don't already have that.

Most sane distributions do this by default nowadays.  I don't use sendmail 
on production boxes anymore, so I don't know if Red Hat or Fedora Core do 
that or not.

-j

  -- 
Jeremy L. Gaddis, MCP, GCWN             jeremy at linuxwiz.net
LinuxWiz Consulting                     http://linuxwiz.net