#infosec How to block an ongoing dictionary attack / brute force attack against Windows Servers, #MSexchange and more

Syspeace - intrusion prevention for Windows servers

Syspeace website

How to block an intrusion attack against Windows Servers for free

If your server or datacenter is targeted by a brute force attack a.k.a dicttionary attacks , it might be hard to figure out how to quickly make it stop.
If the attack is from a single IP address you’d probably block it in your external firewall or the Windows Server firewall and after that start tracking and reporting the attack to see if needs following up.
However, if the attacks is triggered from hundreds or even thousands of IP addresses, it will become basically impossible to block all of them in the firewall so you need something to help you automate the task.

This is where Syspeace comes into play.

Fully functional, free trial for bruteforce prevention

Since Syspeace has a fully functional trial for 30 days, you can simply download it here ,install, regsiter with  a valid mail address, enter the licensekey into the Syspeace GUI and the attack will be automatically handled (blocked, tracked and reported) as soon as the Syspeace service starts up.

In essence, the attack will be blocked within minutes from even connecting to your server.

The entire process of downloading, installing and registering ususally only takes a few minutes and since Syspeace is a Windows service it will also automatically start if the server is rebooted.

If the attack is triggered to use just a few login attempts per attacking IP address and for a longer period of time in between attempts, I’d suggest you change te default rule to monitor for failed logins for a longer triggerwindow , for example 4 days so you’d also automatically detect hacking attempts that are trying to stay under the radar for countermeasure such as Syspeace.

The Syspeace Global BlackList

Since Syspeace has already blocked over 3.6 Million attacks worldwide , we’ve also got a Global Blacklist that is automatically downloaded to all other Syspeace clients.

This means that if an IP address has been deemed a repeat offender (meaning that it has attacked X number of Syspeace customers and Y number of servers within Z amount of tme), the attackers IP address is quite likely to already be in the GBL and therefore it will be automatically blacklisted on all Syspeace-installations, thus making it preemptively blocked.

Syspeace does not simmply disable the login for the attacker, it completely blocks the attacker on all ports from communicating with your server so if you’ve got otther services also running on the server (such as an FTP or SQL Server) the attacker will not be able to reach any if those services either. The lockdown is on all TCP ports.

More Syspeace features, supported Windows Server editions and other services such as Exchange Server, Terminal Server, SQL Server …

You will also get tracking and reporting included immediately for future reference or forensics.
Syspeace supports Windows Server editions from Windows 2003 and upwards, including the Small Business Server editions. It also supports Terminal Server (RDS) and RemoteAPP and RDWeb, Microsoft Exchange Serevr including the webmail (OWA) , Citrix, Sharepoint,
SQL Server and we’ve also released public APIs to use with various weblogins. All of this is included in Syspeace. Out of the box.
We’ve got a IIS FTP server detector in beta and also a FileZilla FTP Server detector and we’re constantly developing new detectors for various server software.

Download and try out Syspeace completely free

Even if you’re not being attacked by a large brute force attack right now, you can still download the trial and have Syspeace handle attacks for you in the background. Who knows, there could be more invalid login attemtpts than you think, such as disabled or removed users that have left the company or very subtle, slow dictioanry attacks going on in the background that actaully might be quite tricky to spot if your not  constantly monitoring logfles.

On this blog, http://syspeace.wordpress.com ,we’ve written a lot of blog articles on how Syspeace works and a lot of other articles regarding securing your servers that we hope you’ll find useful.

Windows server intrusion prevention for hosting providers and cloud service providers with Syspeace

Syspeace - intrusion prevention for Windows servers
Syspeace website

Moving to the cloud or a service provider

The more users and companies start using any kind of external hosted environment, whether it is a cloud serviced VPS, a hosted Exchange, SQL Server or Terminal Server or just a co-located server, the more responsibility will fall upon the service provider to ensure their customers data is protected from unwanted logins and have adequate reporting mechanisms in place.

A service provider will have firewalls in place. They will have monitoring of bandwidth, resource usage, hardware monitoring and probably some antivirus solution but one area that most service provider tend to ignore is intrusion detection on the host level.

PLease refer to this earlier blog post on why the standard methods are NOT adequate for maintain a secure environment, regardless of your a service provider or you host and manage your own servers http://syspeace.wordpress.com/2013/07/11/using-various-brute-force-and-dictionary-attack-prevention-methods-to-prevent-hackers-and-why-they-dont-work-repost/

Verify your providers security awareness

I personally encourage any users / companies having their server hosted elsewhere to actually verify how the service provider handles intrusion attempts.

Try using your login name but the wrong password and simply try to login multiple times to for instance the Exchange OWA Webmail or your Terminal Server / Remote Destop / RemoteAPP Server / Sharepoint / Citrix.

What will happen ? Will you be blocked out and automatically handled as an intruder? Is your account locked out ? Are you alerted in any way by your provider that someone has tried to access your account ? If not, you should ask your provider hos this is possible? Isn’t that one of the ideas of having someone else handling your data and security that they also act upon it and have mechanisms in place for it ? Can they provide you with information on for instance from where your account has been logged in for the last 6 months?

Another interesting side of having your servers handled by others is the reporting capabilities.

When you had your servers in-house, you could verify user logins locally (assuming you’ve enabled auditing for it) but once you’ve handed over control of the WIndows server itself or if you’re in a shared environment, this can become quite tricky to get hold of.

Say for instance you want to verify if a specific user has been logged in and actually worked during July and August ? You also want to know from where? Can your service provider get you this information easily? In some cases, probably yes, not easily but with some manual labor and an extra cost for you, they can get parts of the informtion for you.

Are there any statistics provided by your provider on how many intrusion attempts that are actually blocked by them ? Probably not since this could scare customers away if they don’t have the appropriate solutions in place for securing their customers.

Cloud services and moving your servers to hosting providers and managed services are a great way of cutting costs and getting the benefits of shared environments but you should also demand that intrusion detection is in place, that reporting can be easily arranged from the cloud provider or service provider before even considering using external services. The idea is to get a heightened security , not a lowered one.

If you’re talking to a provider, simply ask them if they’ve thought of these questions and if they have, what countermeasures d they use and what processes do they have in place for intrusion attacks?

If they’re not aware of the problems or even worse, ignore them, maybe you should consider talking to another provider or have them take a look at Syspeace.

I personally believe that using Syspeace will become an advantage for any cloud service provider, hosting provider or outsourcing provider and it will cut administrative costs, strengthen security and be a selling pitch for customers that your using Syspeace to protect your customers from intrusion attemts and dictionary attacks.

Syspeace is not specifically targeted for Cloud providers but should be installed on any Windows based server as part of the baseline security, regardless if it’s a physical server or a virtual server.

By Juha Jurvanen – JufCorp

Intrusion prevention for Windows – Syspeace 2.3.1 released today!

We’re happy to annonunce that we’ve released 2.3.1 today!

The new release fixes some issues with reporting, non English OS, better error handling with communications failure to the license server and other fixes

See the Syspeace website for a free, fully functional trial for intrusion prevention for Windows Servers, Exchange Servers, SQL Servers , Citrix, Terminal Server and more

Syspeace - intrusion prevention for Windows servers
Syspeace website

Using various brute force and dictionary attack prevention methods to prevent hackers – and why they don’t work . Repost

This is actually a repost on a fairly well read blogpost but I thought I’d share it with you again.

Intro on brute force / dictionary attack prevention tactics and some common 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 / dictianary attack 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 you choose not to use what I suggest, I highly recommend that you start thinking about these things properly because these problems will accelerate in the future. Just take a look at all the hacktivism with 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.

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 - intrusion prevention for Windows servers
Syspeace website

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

Syspeace for protecting WordPress from brute force attacks?

A lot of the Google searches now are about the ongoing brute force attacks on WordPress installations.

Syspeace does not, at the moment anyway, support WordPress specifically but here’s an idea I just got.

A Google search on WordPress and Active Directory gave a link to a WordPress Active Directory plugin and that gave me an idea.

In all fairness, I haven’t actually tried this out but the idea is that if you’ve intergrated your WordPress with your Active Directoy, an invalid login attempt should render the correct login failure event for Syspeace to find and therefore be able to stop the attack.

As I said, we haven’t tried it since we don’t have a WordPress installation up & running but if anyone’s up for trying the theory, feel free to download the free Syspeace trial and test it.

If you’re up for it, drop us an email and let us know if it worked?

by Juha Jurvanen