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Brute force attacks prevention on Exchange Webmail OWA with Syspeace

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Syspeace – 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 up 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

#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

Syspeace, SHA-2 certificates and Windows Server 2003 | Syspeace

http://www.syspeace.com/news/syspeace,-sha-2-certificates-and-windows-server-2003/

#eBay hacked ? Sending #trojans according to #FSecure

So. Today I went to a customer site and we’re using #Fsecure there.
All of sudden a user unexpectedly got a virus-warning about a trojan that seems to originate from #Ebay. Of course #Fsecure caught it and I did get a seconf email about a virus from eBay ..
During the weekend he had ordered stuff from #Ebay but his order-history was gone and when he tried to check from the workstation here at the custiomer site he got that virus-warning .

Basically. Stay off #Ebay for a while until you know for sure.

I can’t say for sure they’ve been hacked but I can’t say for sure they haven’t either.

Juha Jurvanen

#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.

#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.

Using locally attached USB drives to #restore #Windows Server 2008 R2 as #DisasterRecovery or shifting servers?

I’m pretty sure this goes for any Windows Server version from Windows Server 2008 and upwards really.

If you’re not up for reading the entire article , the short answer is. Don’t . Please read this previous article I wrote on using Windows Server backup and network shares instead.

Here’s the scenario I had last night.

The plan was to simply shift some servers from older ones to newer ones.
In this case from some older HP Proliant Servers to some newer DELL Servers.
Using backup / restore is a nice method if yo’ve done it earlier (you’ll always run into unexpected stuff if you haven’t done it). Basically the idea is that you donät have to reiinstall all software and settings but simply do a complete Disaster Recovery of the server and fix any hardware issue afterwards. It’s much quicker than installing a new Windows Server from scratch, applying all patches, installing all the software on it, restoring the data for them it and remembering server shares, any special configurations and so on.

The scenario was on the servers to be shifted, there were locally attached USB drives that took a backup every hour of the server. The backups were really quick (since they’re block based, delta and used the VSS ) and everything seemed fine.

The plan was to boot up on a Windows Server Server 2008 R2 Server install DVD / USB drive and simply choose “Repair my computer”, attach the USB drive and simply choose the lates backup image and restore.
A good plan. A great plan even. The result.. well.. not so much.

After booting up on the DVD we hade some read-issues of the DVD first of all. We tried it on several servers and it simply stalled on the “Setup is starting…” . We created new DVDs , same issue. Just one of those weird things that happen sometimes.
Well, not a an issue really. Let’s go for USB stick/drives instead. We created a bootable Windows Server 2008 R2 USB drive and things were looking upward.

Booted on the USB-stick/drive, chose “Repair my computer” and attached the USB disk where the backups are.
Nothing really happened. It just seemmed to be searching the drive for backups and eventually timed out with an error message abu the “Backup wizard being open for too long” and blablabal. No backups to choose, thus , nothing to restore.

On the USB drives, there were a few hundred generations backups, automatically done by the built in Windows Server Backup.
So, for trouble shooting, we attached the drive to a running server and there’s nothing wrong with the disk. We could browse the filesystem and see the WindowsServerImagebackup and everything. Things just got stranger.

As a troubleshooting thing, we decided to see what happens if we try to choose to do a restore from a server that we weren’t go to shift but that was using the same backup method, that is, a locally attached USB disk, dedicated for backups and the backups were automatically run every hour to it.

Interestingly enough, everything seemed fin (all backups had ran succesfully and so on, absolutely nothing pointed to any errors) but when choosing the “Recover once” option we had exactly the same symptoms. It just stalled searching for backups and eventually timed out.

Now we realized that this is not a good way to do backups, although everyting seems ok according and to the backuplogs.

So, the workaround then . Here’s what we did.

1. We created a new, complete backup to a network share (excluding any USB drives of course)

2. We booted up the server with a USB stick, “Chose repair my computer”, and Advanced to attach to the network s image to share where the backups are.

3. Restored the server 🙂 . Oh, the joy.

4. Disconnected it from the network, rebooted, Set up the same IP address as the original had (since there’s new networks cards this has to be done manually), shut down the old server, attached the new and estored server to the network and we were good to go. Everyhing was ok. All servicesa could be started, the Intrusion Prevention worked immediately (Syspeace) and all communications woith other servers was ok.

Here’s a quick how to and what you’ll have to keep in mind when restoring from a network share

A few things to keep in mind when restoring from a network share and booting up in a USB sick though.
* Make sure you have DHCP server on the same network

* After selecting the backupimage to restore, REMOVE the USB Stick you booted from . Even if you choose to exclude drives from the restore process (in the advanced section I think it was) you’ll get an error message stating “Incorrect prameter” if the USB stick is still attached. A bug. feature ? Don’t know what to call it really. Weird. I’ve seen it everytine I’ve done this so now I’m used to it.

* When rebooting the server,you may end up a server that want’s to be repaired so you’ll need to have the LOCAL administrator password for it or söme kind of software to help you fix any hardware diferences. I’ve got a favourite with Evault’s BMR that’s a great and easy to use tool to get the job done quickly but not everyone has access to it.

* When the server is up & running and you’ve set the correct IP address and stuff, be sure to remove any devices no longer present in the new server by starting a command prompt and entering:
c:> set devmgr_show_nonpresnet_devices=1 [ENTER]
c:> devmgmt.msc [ENTER]

Choose to “SHow hidden devices” and remove any device that’s “greyed out”

Now, you should be good to go. It worked flawlessly for us last night, apart from that we spent hours and hours trying to understand why we couldn’t use the locally attached USB drives that contained the backups.
In this case, it was a good thing that it wasn’t a Disaster Recover scenario so it wasn’t the end of the world really but if it had been, I wouldn’t be laughing really.

By Juha Jurvanen @ JufCorp

JufCorp website

JufCorp

How to battle slowgrind #bruteforce attacks against #msexchange #windows server #remotedesktop #sharepoint with #Syspeace

Syspeace automatically blocks attacks that occur according to the rules.
The default rule is that if an intruder fails to login more than 5 times within 30 minutes, the intruders IP address is blocked, tracked and reported for 2 hours and simply is denied any access to the server.

A new trend though has emerged and that is for bruteforce attackers to “slowgrind” through servers, trying to stay “under the radar” really from IDS/IPS HIPS/HIDS such as Syspeace.
They’ve got thousands and thousands of computers at their disposal so they’ll basically just try a few times at each server and then move on to next one in the IP range or geographical location hoping not to trigger any alarms or hacker countermeasures in place.

An easy way to battle this is actually simply to change the default rule in Syspeace from the time windows of 30 minutes to for example 5 days.

This way , I’m pretty sure you’ll see there are quite a few attackers that only tried 2 or three times a couple of days ago and they’re back again but still only trying only a few times.

With the “5 day” windows, you’ll catch and block those attacks too.

Here’s actually a brilliant example of an attack blocked, using a 4 day window.

Blocked address 121.31.114.99() [China] 2014-08-11 15:06:00
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:
        2014-08-11 13:05:51     aksabadministrator
        2014-08-10 22:06:48     aksabadministrator
        2014-08-10 06:39:12     aksabadministrator
        2014-08-09 15:39:52     aksabadministrator
        2014-08-09 00:32:05     aksabadministrator

Syspeace has blocked more than 3 285 300 intrusion attempts against Windows Servers worldwide so far.

Syspeace - intrusion prevention for Windows servers

Syspeace website

#infosec Over 3.1 Million bruteforce attacks against #windowsserver #msexhange #Sharepoint #remotedesktop #Citrix blocked by #Syspeace

Syspeace , intrusion prevention for Windows servers,  has blocked,tracked and reported over 3.1 Million bruteforce and dictionary attacks targeted worldwide at Windows Servers running Remote Desktop , Exchange, Citrix, Sharepoint, SQL Server and other services.

image

#Syspeace stops due to license server inaccessable on #Windows Server 2003 #infosec

Syspeace service stops due to license server not reachable / inaccessibility on Windows Server 2003

We’ll actually update the troubleshooting section with info for Windows 2003 Servers but here’s why this can occur.

Apparently root certificates are not automatically updated on Windows Server 2003:

http://support.microsoft.com/kb/931125

> The automatic root update mechanism is enabled on Windows Server 2008 and later versions, but not on Windows Server 2003. Windows Server 2003 supports the automatic root update mechanism only partly. (This is the same as the support on Windows XP.) And because the root update package is intended for Windows XP client SKUs only, it is not intended for Windows Server SKUs. However, the root update package may be downloaded and installed on Windows Server SKUs, subject to the following restrictions.

> If you install the root update package on Windows Server SKUs, you may exceed the limit for how many root certificates that Schannel can handle when reporting the list of roots to clients in a TLS or SSL handshake, as the number of root certificates distributed in the root update package exceeds that limit. When you update root certificates, the list of trusted CAs grows significantly and may become too long. The list is then truncated and may cause problems with authorization. This behavior may also cause Schannel event ID 36885. In Windows Server 2003, the issuer list cannot be greater than 0x3000.

This can be resolved for Syspeace by manually installing the gd-class2-root.crt certificate from this page: https://certs.godaddy.com/anonymous/repository.pki