Timothy,

I think you have finally hit on the magic words: "This is a very clean
install, just iis, iMail [and] Sql on the box, as it is to be kept clean
being used as a development server."

If you are running IMail on the box, then you should NEVER have IIS
installed at the same time.  They cannot comfortably share port 80 unless
you go about enabling that setup EXACTLY the right way.

The other issue here is the SQL install.  There are numerous known hackers
issues with both IIS and SQL.

If you are running Windows NT or 2000, did you REMOVE the EVERYONE group
completely from all of the directory permissions BEFORE you installed IMail?
(see how to do that in the article I have included below).

The company I own, ChicagoNetTech, recently purchased a company called
Rinella Internet Services.  Rinella Internet Services was (and still is)
ruining IMail.  We initially thought about switching all of the user
accounts on them to another product and decided against it after giving
IMail a thorough look.  In fact, we have been negotiating the purchase of
Rinella for almost 18 months and joined this group as part of our research
on the purchase of the company,

They also had several problems relating to spam and relaying that were not
totally resolved by just using the built in solutions that IMail provides.
After some substantial research, we found that the server they were running
the IMail software on was providing the opportunity for the hackers and
spammers to get in via the security loopholes in the OS.

Here is a document from the former head of It Security for the US Secrete
Service that discusses Windows 2000 Security - much of what he says is also
pertinent to Windows NT as well.

This was originally published in a newsletter that I get from a group I am a
member of and I am passing it on to you (and everyone else on here) because
it is extremely important to have your SECURITY properly setup on any
machine BEFORE YOU INSTALL ANY SOFTWARE on the machine.

Here's my suggestion to solve your problems:

  1: Completely wipe the machine of everything. - REFORMAT ALL OF THE HARD
DRIVES and START OVER.

  2: Install your OS and apply the security instructions included in the
article below

  3: Install ALL MICROSOFT SECURITY PATCHES

  4: Install SQL SERVER

  5: Install SQL SERVER Service Pack III

  6: Check the Windows UPDATE web site.  Scan for UPDATES and install ONLY
the CRITICAL UPDATES.  DO NOT INSTALL ANY of the .NET updates.  DO NOT
install any of the language packages that you don't absolutely require.

  7: Get rid of any GAMES, video players, ENTERTAINMENT software, coding
software and any other software that auto-installs on the server and check
for patches AGAIN to make certain you haven't removed anything.  Remember, a
server should NEVER be simultaneously used as a workstation.

  8: REINSTALL Windows 2000 Service Pack 3 - if you have added or changed
anything since your original install, it is quite possible that you have
overwritten some of the updated files.

  9: Install IMail and configure your main domain.  If you have any virtual
domains, then configure them as well.

10: Test your IMail server.

11: RENAME your GUEST ACCOUNT to something other than guest.

12: Do not allow anyone who doesn't absolutely need to log into the server
to have a login on that server that is enabled as a "login locally to
server" account.

13: Do not install any shared printers to this machine.  It is OK to install
a printer that is located on another machine, but change the permissions on
the printer so that NO ONE can use the printer on the server except the
SYSTEM and the ADMINISTRATOR.

Bruce Barnes, CEO
Rinella Internet Services, Chicago IL



Here is the article from Mike Mullens, former Assistant Network
Administrator for the US Secret Service.

REMEMBER - ALWAYS MAKE A BACKUP COPY OF YOUR REGISTRY BEFORE MAKING CHANGES
TO THE REGISTRY!

----------------------------------------------------------------------------
-----------------------

PLAY BY THE RULES FOR WIN2K SECURITY

Security fixes and patches are useless if your Windows 2000 server is placed
on the network without a secure configuration. You can significantly reduce
your server's vulnerability and eliminate denial of service attacks by
following seven simple rules.

RULE 1

Remove all unnecessary programs and Windows Components. You can do this via
the Control Panel's Add/Remove Programs module. (Why patch a service or
program that shouldn't be running in the first place?)

RULE 2

Disable unneeded services. A significant number of services and background
processes are installed and started by default; disable any services that
aren't absolutely necessary for your server's everyday performance. This is
done via the Services module under Administrative Tools.

For a complete listing of Windows 2000 services and a description of their
purpose, take a look at Microsoft's Glossary of Windows 2000 Services.
http://www.microsoft.com/windows2000/techinfo/howitworks/management/w2kservi
ces.asp

RULE 3

Change User Rights. By default, User Rights is wide open. Close this hole
with the following recommendations for specifying Group or User rights.

1. Access this computer from the network--Remove the Everyone Group and
replace it with a group that's more restrictive, such as Authenticated
Users. [NOTE:  Make certain you ADD the AUTHENTICATED USERS group BEFORE you
delete the EVERYONE group,  You need to do this with EVERY LOGICAL DRIVE

2. Bypass Traverse Checking--Remove the Everyone Group and replace it with
Authenticated Users.

3. Create Permanent Shared Objects--Replace with Administrators Group only.

4. Logon Locally--Replace with Administrators by username and Service
Accounts. I recommend by username because this creates an additional
security mechanism in case a rogue user tries to gain console access with a
tool that escalates the user's privilege to Administrator.

5. Shutdown System--Replace with Administrators Group only.

RULE 4

Synchronize your clocks and enable auditing. If you're going to compare logs
from different systems after a security incident, all of your systems must
have the same time. Auditing will track changes to your system when employed
properly. At a minimum, audit these events for both Success and Failure:

* Account logon events
* Account management
* Directory service access
* Logon events
* Object access (monitor for failure only)
* Policy change
* Privilege use
* Restart, Shutdown, and System

RULE 5

Disable unnecessary file sharing. Unless absolutely necessary, remove hidden
drive letters and remote admin shares (ADMIN$, C$, D$, etc.). To remove
these admin shares permanently, set the registry key AutoShareServer
to 0. This key is found at:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\LanmanServer\Parameters

If the key isn't present, add a value of type REG_DWORD and set that to 0.
This permanently disables all automatic hidden shares. 

RULE 6

Set and enforce strict file level and registry permissions. Go through your
directories and verify that only specific groups have access to the
information contained within them. Restrict anonymous users from accessing
the registry. This can be done by a registry key:
HKLM\System\CurrentControlSet\Control\LSA\restrictanonymous

Or via a Group Policy:

Group Policy\Computer Configuration\Windows Settings\Security Settings\Local
Policies\Security Options\Additional restrictions for anonymous connections

The values for the registry key or the Group Policy Object are:

1=Do not allow enumeration of SAM accounts and shares.
2=No access without explicit anonymous permissions.

RULE 7

Minimize your servers' exposure to denial of service attacks. Windows 2000
allows you to adjust the TCP/IP parameters to have greater control over
connection state. Take advantage of this by modifying the following hive
with these registry entries:

HKLM\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters

1. SynAttackProtect: REG_DWORD=2. Drops third packets of the TCP/IP
handshake in an attempt to consume available session handles.

2. TcpMaxHalfOpen: REG_DWORD=500. Limits the number of half-opened TCP
sessions.

3. EnablePMTUDiscovery: REG_DWORD=0. Prevents the use of nonstandard Path
Maximum Transmission Unit size for all external connections.

4. Netbt\Parameters\NoNameReleaseOnDemand: REG_DWORD = 1. Prevents an
external host request for the server's NetBIOS name.

5. EnableDeadGWDetect REG_DWORD = 0. Prevents a server from switching
gateways and allowing an attacker to hijack a session.

6. EnableICMPRedirects: REG_DWORD = 0. Prevents an external host from
modifying the server's routing table.

7. DisableIPSourceRouting: REG_DWORD=1. Disables client source routing
attempts.

Patching a poor configuration is useless until you add the first layer of
security to your operating system: Locking down the operating system is the
start of any deployment. After your operating system is secure, verify that
your server isn't listening on any ports that aren't integral to its
day-to-day operation and block all nonessential traffic from the Internet to
your system. Security is a layered approach, and this list is by no means
complete. But it's a start to hardening Internet-exposed servers.

NOTE: Be sure to back up the registry before editing it so that you can
restore it if something goes wrong.

Mike Mullins has served as a database administrator and assistant network
administrator for the U.S. Secret Service. He is a Network Security
Administrator for the Defense Information Systems Agency. 

---------------------


-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Timothy
Hunold-Cre8ive guy
Sent: Monday, February 17, 2003 00:57
To: [EMAIL PROTECTED]
Subject: RE: [IMail Forum] imail, meltdown


Weblogs just show me logging in, or trying to, that is when I realized that
my web was down. Why would a dictionary attack cause web to crash, it would
be more efficient to do it via pop3... You would have to be doing post
commands all day long.

Why google? I would get vague info... The specific info I am seeking is as
it pertains to imail. I had used Kendra, and other dictionary attacks to
test my own servers back on v6.04... but at the same time, that was not
spawing email. I have all mail cc'd to another account, and I get all sorts
of stuff on Chinatimes, and other far eastern asia related topics. Seems
like it is relaying, and even if it is a dictionary attack, I find think it
might take about 100 years to reach my password in mixed case, and it also
is an acronym for a very highly specific industry term, along with a
sequence of numbers. It is the kind of thing that will never occur in any
language.

I guess it sounds like a game of who can hold their breath longer. But in
the meantime, my server has been under attack for 2 weeks.

I want to know why webmail keeps crashing after i change the ports at
random?

This is a very clean install, just iis, imail sql on the box, as it is to be
kept clean being used as a development server.
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Jason Newland
Sent: Sunday, February 16, 2003 10:38 PM
To: [EMAIL PROTECTED]
Subject: RE: [IMail Forum] imail, meltdown


As I said before, you are seeing a dictionary attack, nothing else.  There
are several ways to stop or reduce these, just google for dictionary attack.
A 9 meg smtp log file isn't overly large, but in order to "prove" your
original theory correct, we need to see the web logs where your attacker is
doing the attacking.....

<<attachment: winmail.dat>>

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