#msexchange Brute force attacks prevention on #Webmail #OWA with #Syspeace #hacking #security

Syspeace icon
Syspeace icon

Preventing brute force attacks against Microsoft Exchange Server and OWA Webmail

If you’re running Microsoft Exchange Server your also quite likely to have the Microsoft Exchange OWA (Webmail)
interface up & running to enable your users to use Activesync and access their email, calendars and contacts
over an easy-to-use web interface accessible over the Internet. This is just as relevant if you’re managing your
own Exchange Server or if it is a hosted Exchange at a service provider. If your provider doesn’t have a
solution for this, you may find yourself in a very difficult situation one day as explained further down.
Since the Exchange Webmail (OWA) is reachable and visible over the Internet, this of course also means that
anyone is able to try to log in to your Exchange server over the same OWA interface. They may not succeed to
login but they may try to overload your server by sending lots of login request or have your users undergo a
Denial of Service attack (a DoS attack).

Brute force attacks used as Denial of Service attacks

The OWA in itself (or does Windows Server for that matter) doesn’t have any brute force prevention mechanisms
built into it but the actual user validation is done within the Active Directory infrastructure by your domain
controller(s). Within the Microsoft line of products this is actually true for most of them such as Terminal
Server (RDS, Remote Desktop), Sharepoint, SQL Server and so on and also for Citrix since user validation is done
in the same way.
If you have for instance set up Account Lockout Policies to disable a user account after 5 failed attempts ,
anyone with knowledge of your name standards (email addrees, AD login) can basically run a script against the
server using a specicif username (or hundreds of them) and deliberatley usoing wrong passwords, thus locking the
legitimate users account and disabling them from loging in at all (in essence, they can’t even login to anything
that uses the Active Directory validation, not even their own workstations in the Office)
If such an attack is made from a single IP address, it is fairly easy to block it manually (simply block the
attack in either the external firewall or the local firewall of the Exchange server).
In reality though, this is not how such an attack occurs. Should someone really want to disrupt ypur services,
they will do this from hundreds or thousands computers at the same time and making it impossible to block
manually.

Using Syspeace as a countermeasure

With Syspeace , this is all taken care of automatically. Syspeace monitors the Windows Serevr logs for failed
login requests and if an IP address tries to login against your servers ( Exchange, Terminals Server and so on)
and fails for instance 5 times within half an hour, the IP address is automatically blocked from communicating
at all with the affected server on any level (so if you’re also running other services , they will not be able
to target them either once blocked).
Each attack is blocked, traced and reported via email that contains the source IP address, the username used,
country of origin and previous attacks from the same IP address.

Here is actually an example of how the email notification looks like (with IP address and domain name intentionally removed)
Blocked address *.*.*.* (ip-*-*-*-*.*.secureserver.net) [United States] 2015-01-14 18:45:00 Rule used (Winlogon):
Name: Catch All Login
Trigger window: 4.00:30:00
Occurrences: 5
Lockout time: 02:00:00
Previous observations of this IP address:
2015-01-14 16:44:50 ****lab
2015-01-14 16:44:52 ****labroator
2015-01-14 12:53:44 ****ron
2015-01-14 12:53:46 ****demo
2015-01-14 12:53:48 ****canon

Syspeace also delivers daily and weekly reports of blocked threats.

Within Syspeace, there is also reporting tools for access reports, a Global Blacklist for infamous offenders and
much more.

Installing and setting ups Syspeace

Setting up Syspeace is very easy and only takes a couple of minutes, without the need for changing your
infrastructure or bying very expensive dedicated hardware. Most likely , you will not even need to hire a
consultant for it.

Syspeace runs as Windows Service and support a variety of Windows Servers such as Terminal Server, Exchange Server, Sharepointm Windows Serevr 2003 to Windows Serevr 2012 R2 and more and it starts detecting brute force attacks immediately after you set it up and press the start button.

Please download a free, fully functional 30 trial from http://www.syspeace.com/free-download/download-plus-
getting-started-with-syspeace/
and see for yourself how a very big problem can be very easily solved.
Should you decide to keep using Syspeace, the licensing cost is equivalent to an antivirus product and the
licensing model is highly flexible, enabling you to decide for yourself ofor how long you wish to run Syspeace.

Syspeace - intrusion prevention for Windows servers
Syspeace website

#infosec Moving #Syspeace licenses between servers

The Syspeace licensing model is a flexible and easy to use model.

The license you used for the free trial is automatically converted into a live a license when you purhase a license. You don’t need to reconfigure.

You decide for youself if you want use Syspeace for a year at a time or for example 2 months and on how many servers you want to divide the number of computerdays.

You can use the same licensenumber on multiple servers and the central licensing server keeps track of licensing for you and you can easily extend you existing license.

If you need to move the license from one server to another, simply start the Syspeace GUI, find the reset license button and reset. Install Syspeace on the new server and you’re good to go.
Another way is to simply stop the Syspeace service on the old server and install on the new server, using the same licensenumber.

All updates and new, generic detectors are free to download for valid licensesowners and trialusers.

If you’re hosting servers or have many servers the easiest approach is probably to have one Syspeace account and use the same license for all servers but if you’re managing multiple external servers you’d probably want to have a separate Syspeace account for each customer for instance ACME @ YourCompany.
This way you’ll easily keep track of the administrative part with your invoicing.

By Juha Jurvanen @ JufCorp

#Infosec When and where is Syspeace useful for intrusion prevention ?

In what scenarios Syspeace is useful for preventing brute force attacks? Do I need it if I’ve only got a Windows workstation?

Syspeace - intrusion prevention for Windows servers
Syspeace website

Syspeace is an intrusion prevention software mainly targeted for Windows Servers, SBS Server, RDS TS Servers, RDWeb, Sharepoint Servers, SQL Server, Exchange, Sharepoint, Citrix and so on but it will also run on Windows 7 and above for home use.

To have a real use for Syspeace these conditions need to be met

1. You need to have enabled remote access to your server / workstation.

2. You need to have set up some kind of portforwarding in your external firewall to your server / workstation. If you are for instance on a standard broadband connection and you haven’t done anything with the default rules in your boradband modem, your workstation is probably not reachable from the Internet thus making a Syspeace installation quite unecessary and waste of RAM and COPU for you, minimal of course but still. There is no need to have software installed in any computer environment that actually doesn’t do anything for you. It’s a waste of resources.  

3.The same goes for servers although in a server environment you might want to have Syspeace installed to monitor and handle internal brute force attacks since Syspeace works just as efficently whetheter the attack is externla or internal. It will even block a workstation trying to connect to netowrk shares via the command prompt using ”net use * \servernamesharename” command. Have a look at his entry for instance http://syspeace.wordpress.com/2013/09/25/syspeace-for-internal-brute-force-protection-on-windows-servers/

4. There could be a scenario where you have for instance your own hosted WorPress Blog that is reachable from the Internet . Please refer to http://syspeace.wordpress.com/2013/04/24/syspeace-for-protecting-wordpress-from-brute-force-attacks/ for an idea on brute force prevention for WordPress Blogs.

5. In server envirenments you might have Syspeace installed not only for intrusion prevention but also to have a good reporting on various user login activity that can be viewed and exported in the Access Reports Section.

6. If you’re using mainly Cloud Services or a managed VPS ,the intrusion prevention should be handled by your Cloud Service Provider . Here’s an older blog post on how to have verify how your provider handles hacking attacks : http://syspeace.wordpress.com/2012/11/19/securing-cloud-services-from-dictionary-attacks-hack-yourself/

There is a fully functional, free 30 day trial for download at http://www.syspeace.com/free-download/download-plus-getting-started-with-syspeace/ .
Give it a try and have your Windows Server instantly protected from dictionary attacks and brute force attacks. The installtion is small, quick and very easu to set up. You’re up & running in 5 minutes and there’s no need to chnage your current infrasctructure, invest in specific and usually expensive hardware or hire external consultants.

By Juha Jurvanen @ JufCorp

Tha brand new Syspeace website – now also with worldwide hacking statistics

Finally, the new website is up!

We’ve launched our new website a few weeks back and some of the news, apart from a better design and easier naviagtion, is that we’ve also included a security status page to display statistics based on Syspeace installations that report each hacker attack around the world.

Have a look for yourself at http://www.syspeace.com/security-center/security-status/ . You might find something interesting in there.

The statistis are dfivided into to two columns. The originating country for the attack and the country from where the Syspeace installation reported the attack.

The statistiscs displayed are the last 30 days of hacking attacks and so far Syspeace has blocked more than 1.4 Million brute force and dictionary attacks against Windows server worldwide!

While you’re at the website, download a free, fully functional trial to ptotect your Windows servers, Exchange servers, Terminal / Remore Desktop Services servers, Citrix servers, Sharepoint serevrs, SQL servers and more from brute force and dictioanry attacks.

Syspeace supports Windows Server 2003, Windows Server 2008, Windows Server 2008 R2, Windows Server 2012 and the Windows Server Small Business editions.

By Juha Jurvanen

Various brute force prevention methods for Windows servers – pros and cons

Intro on brute force prevention tactics and some misconceptions

Protection from brute force attempts on Windows servers has always been a nightmare and would continue to be so if not .. Yes, I admit, I will come up with a solution further down.

Most system administrators with selfrespect start off with the best of intentions to actually keep track of brute force attempts but eventually give up because of the sheer number of attacks that occur daily.

Others, unfortunately, believe that a firewall takes care of the problem which it doesn’t or that an account lockout policy is the answer. Neither of them is and I’ll show you why.

The firewall approach:

Think about it. What does a firewall actually do ? The role of the firewall is to block traffic on unwanted ports and to drop portscans and variuos SYN FLOOD attacks. That’s about it. A firewall is basically a harsch doorman deciding who gets in to speak with the guys on the inside and who doesn’t.

If an attacker actually connects on a valid port , the traffic is redirected/port forwarded to the server in question let’s say the webmail interface of a Microsoft Exchange Server or a Microsoft Windows Terminal Server or a Citrix Server. Once the attacker is there, the actual logon request is handled by the server,not the firewall. The logon process is managed by the Windows Authentication process (which in turn may be validated against Active Directoy or a local user database using SAM). The firewall is already out of the picture really since it has no connection with the Windws server apart from  the TCP connection and keeping it alive really. They don’t communicate the result of the logon process between eachother.

Also, a changing of from standard ports won’t help you much, will it ? The logon process is still managed by the Windows Server although you will get rid a of a lot of portscans and ”lazy background, script kiddie attempts” if you’re using non standard ports. Basically you get rid of the script kiddies but the problem isn’t solved, the traffic is still redirected/port forwarded to the server that does the actual authentication.

Using for instance a Remote Desktop Gateway won’t handle the problem either. Using a RDP Gateway minimizes the attack surface, yes, but it is still reachable and the user logons still have to be validated. The problem is with any server that services logon request basically, regardless of on what ports and how they get there. That is Microsoft Windows server, Exchange Server, Citrix, Sharepoint, CRM , Terminal server and so on . The list can probably go on and on.

There’s also the risk of stuff stops working each time you apply some updates or patches to your Windows Servers if you start changing standard ports or standard configurations. It’s happened to me a few times and it’s not that amusing to be honest when you’ve got 1000 users not being able to log in beacuse you’ve just done your job and patched the servers to keep peolpe datas safe. Trust me, that’s not a good Monday morning.

The VPN approach:

Yes. That’s a safer approach but also here we do have some issues. First of all, it’s not that easy to keep track of VPN certificates, to set all of it up and manage all the licensing costs (that can be quite significant really ) and (sometimes costly) hardware you need to have in place. Historically there has also always been performance issues with most VPN solutions since all traffic is directed through one or a few VPN servers / connectors. Some of them also charge you for the bandwidth you want it to be able to use for VPN connections or charge you for the number of simultaneous VPN connections, A VPN solution can be quite costly as an initial investment and taking into account all of the administration involved in it.

You also probably won’t be demanding your users to have a VPN connection to the Microsoft Exchange OWA etiher snce the whole idea of the OWA i that it’s supposed to easy to reach from anywhere. I know there are some companies actually requiring VPN even for OWA and that’s just fine I guess but the more we’re moving our data and applications to cloud services, this hassle with different VPNs and stuff will eventually be fading into the dark corners of the Internet (that’s my personal belief anyways). The thing is that your users don’t want to be tied down by complicated VPN clients and stuff, users nowdays are used ”stuff just working” and it has to be easy and intuititive for them. The days of the ”System Administrators from Hell” implementing all kinds of complex solutions to keep stuff secure and forcing users to having very specific and complex ways of accessing data are over. They were good times, good times but they’re over. Deal with it.

The IDS/IPS approach:

Using a centralized IDS/IPS This is a more efficient method, yes. The downside is, most of these systems require you to change your infrastructure and get specific, costly hardware, licenses and costly consultants to get it up and running. And someone needs to monitor it, take care of it and so on. There are parllells to the VPN approach here although an IDS/IPS does a while lot more such as examines all the network traffic, examines it for malicious code and so on. I’m not sure actually if an IDS/IPS can communicate with the Windows Server Authentication Process so I’ll actually won’t say anything about that. I would presume they can, otherwise I fail to see the point (from the brute force logon prespective, that is) and you’d still need to handle the logon attempt on the Windows server.

The Account Lockout Policy approach:

The acccount lockout method is also flawed due to the fact that an attacker can quite easily cause a DOS (Denial of Service) simply by hammering your server with invalid logon request but with valid usernames, thus rendering the accounts unusable for the valid users. Basically, all he (or she)  needs to know is the user logon name and in many system , it’s not tha hard to guess (try the companynameusername or the mail address for the user since it’s quite often also a valid logon name if you have a look at the properties of the user in Active Directory Users and Group snap-in)

The Cloud Computing approach

We are shifting  more and more of our data and applications into various Cloud Services (like it or not but, it’s a fact and you know it). This way we do get rid of some of these problems on our own servers and hopefully, your Cloud Service provider actually has a plan for these scenarios and has the necessary surveillance software and systems in place. If you’re using a Cloud Computing platform based on Windows Servers, you should actually ask your provider how they handle brute force attempts on their servers. Most likely they will give you one or more of the scenarios described above and, as I’ve showed you, they are not adequate to handle the task at hand. They’re just not up for the job. Feel free to ask your own provider and see what answer you get. My guess is .. mumbo jumbo but basically , they don’t have anything in place really, more or less.
You could even try logging into you own account with your own username but the wrong password loads of times and see what happens. Will it be locked out? Will your machine be locked out? How does your Cloud Srvice Provider respond and are you informed in any way that an intrsuion attempt has been made using your account ? How many times can anypne try to access your account without you being notifed of it? And from where are they trying to get to your data and why?
Personally I know of only one Cloud Service Provider that has also taken these questions into account and that’s Red Cloud IT in Sweden.

Is there a solution then?

Yeah. I told you so in the beginning and even if choose not to use what I suggest, I highly recommend that you start thinking about these things properly because these problem will accelerate in the future. Just take a look at all the hacktivism witj DDOS attacks,going on out there. It’s just a start because the Internet is still young.

First of all, and this is extremely important you realize, , it doesn’t matter if you hosting your own servers or if you’re using VPS (Virtual Private Servers) hosted somewhere else or even if you’re a Cloud Service Provider. The basic principal stands: if you are providing any kind of service to users using the Windows Authentication mechanism you should be reading this and hopefully my point has come across.

If you’re having brute force attacks on your Windows systems today and I’m pretty sure you do (just turn on logon auditing and I’m sure you’ll see you have more than you actually thought you did, *for some odd reason this is NOT turned on by defaut in Windows*) there’s a few things you should be doing (that I’m guessing you’re not beacuse you’re not a cyborg and you need to sleep, meet your friends and family and actually be doing something productive during your work hours). On the other hand, if you are doing all of these things I’m guessing you have quite a large IT staff with a lot of time on their hands. Good for you. Call me and I’ll apply for a position.

First of all. Block the attack.

You need the attack to stop! Instantly. This is of course your first priority That’s basically blocking it in the firewall, either in the local Windows firewall or the external one, it’s actually up to you which way is the easiest one. The reason is that you don’t want to be wasting CPU and RAM and bandwidth on these people (or botnets)  and of course, you don’t want them to actually succeed in logging on (should you have a lousy password policy in place ) or even them disguising a real intrusion attempt behind a DDOS attack to fill your logfiles and hide themselves in there. (Yes, it’s not an uncommon method). There’s also quite a few reports of DDOS attacks being used to disguise the actual reason for it which is to find out what security measures are in places for future reference. The ”know your enemy principal”.

Second. Trace the attack. From where did it come?

Second , you need to find out from where the attack originated and what username was used. This is because you want to know if it is a competitor trying to hack you and access your corporate data or if you find yourself in the interesting position of your own username trying to login from sunny Brazil and you’re just not in Brazil (although you’d love to be) . You’re in Chicago looking at winter. Somethng’s up.
You also want to see if it’s a former employee trying to log on and so on .. This is stuff you need to know and keep track of since there may be legal issues involved further down the line.

Points one and two , you want to be handled in real time. There’s no use for you to find out two days after the attack that something actually happened. You want it stopped, reported and handled as it happens.

The legal stuff.

Third, you need to decide what to do with your information. Should it be handed over to the legal departement, your boss, the police or is it just ”nothing” and can be discarded ?

So. ”What would you suggest as a solution then” ? 

The easiest and most cost efficient way to handle brute force attacks on Windows server is to have an automated sysem to block, track and report each attack and that’s where Syspeace comes into play.

Syspeace is a locally installed Windows service, thus using a minimum of system resources,  that monitors the server for unwanted logon attempts and blocks the intruders in real time in the local firewall based on the rules you’ve set up. For instance ”if this IP address has failed logging on 20 times during the last 30 minutes then block it completely for 5 hours and send me an email about it”

This means that you can for instance set up a blocking rule that is you ”Account lockout policy – 1” in your rules and that way simply blocking the bruteforce attack but not locking your users accounts and causing them unecesseray disruption.

Since Syspeace monitors the Windows Authentication logon oprocess, it doesn’t matter what firewall your using or what ports you’re using, the monitoring and blocking is done where the actual login attempts is made and therefore caught and handled automatically.

Once the intruders IP address is blocked, it’s blocked on ALL ports from that server which means that if you have other services also running on it (like FTP or well.. anyhting really) those ports and services are also protected instantly from the attacker. Not giving them the chance to find other ways of gaining access to that server through exploits.

A few other features in Syspeace

A few other nice features with Syspeace is for instance the GBL (Global BlackLlist) where every Syspeace installation around the world , reports each attack to a databse where they are examined and weighed and , if deemed ”meneace to Internet and all of mankind” the database is then propagated to all other Syspeace installations. In this way, you’re preemptively protected when the bad guys come knocking on your door. So far , there has been over 200 000 brute force attcks blocked by Syspeace worldwide (and that’s just since mid July 2012) and some of them have made it to the GBL. Lucky them.
Of course there are white lists and stuff, giving you the ability to have your customers or internal users keep hammering you servers all day long if they (and you) want  without being blocked out.

There’s also the Attack Cintrol section that gives you the ability to sort out information about successful and failed logons, findind the ones that are trying to stay under the radar, viewing reports.
You get daily and weekly reports email to you and each attack is also mailed to you with detailed but easy to understand information from where the attack originated including country, what username was used and how many times they actually tried to hack or overload you. This gives you the ability to quickly see of it’s something you should be taking care of or just carry on with your working day and leave it be with a smile on your face.

The GUI is easy to use (and there’s an even easier coming up in the next version) so there’s no need to hire costly consultants to be up & running or start using various scripts and change parameters in them to suite you needs and hope for the best and hope they don’t hang your servers.

Syspeace also protects the Microsoft Exchange Server Connectors from being attacked.

There is a Windows 2003 version coming out and there will be more features added as we go. The roadmap and to-do list is ..well.. extensive to put it mildly.

The licensing is not steep, I’d even dare say cheap and it’s extremely flexible.

As an example. If you buy yourself a new server today (evereybody loves new toys ) , you install Syspeace on it and then you get yourself a second server in 4 months. You can easily align the licensing renewal dates for both servers , not having to keep track of licensing renewals scattered over the entire year. If you’re up for , you could even byt yourslef just a one months license. Or a week. I’s up to you and what needs you have.

Download a free trial and see for yourself.
We know it works and so does all of the people around the world who are already running it.

Syspeace – let the silence do the talking

Syspeace logo
Syspeace – bruteforce prevention for Windows servers
 

Blog post written by Juha Jurvanen
Senior IT consultant in backup, IT securiy, server operations and cloud