Tuesday, 22 September 2015

A Weapon for the Mass Destruction of Computer Infrastructures

Disclaimer: This is NOT a weapon. This is AN EXPERIMENT. 
You MUST NOT try this at home. The tests were performed under the supervision of licensed electricians, in a controlled environment. 
I intentionally do not provide any technical details about the devices. The purpose of this blog post is not to tell you how to do this, but to raise the awareness that this can actually happen. I believe, entities should be aware of this threat and take any necessary actions to protect their infrastructures. 

Having done a number of physical security assessments over the years, I started wondering how vulnerable our computer infrastructures are. I tried to think of a way for a malicious insider or an external third-party, to target a company’s computer network and take it down by damaging it (someone who doesn't have physical access to the server room). I started thinking about this from a different perspective and I tried to approach this "question" with an outside-the-box point of view. 

Due to my experience with physical security assessments I noticed that there are many unattended Ethernet ports (sockets) everywhere around a building. These ports might not be “active” but most of the time they are connected at the far-end on a managed or unmanaged network switch

I started wondering what would be the effect if one tried to apply electric current on an Ethernet socket from a power socket directly. The picture on the left illustrates a cable which sends electric current (220V-250V) directly from the power socket to the Ethernet port (This is very dangerous, do not make one, and do not try to use it). In reality, such attempt is actually pointless, as it will only "toast" the device you connect this modified power cable. 

The hypothetical network switch at the other end will end up toasted in a split second and the person doing this will experience a loud bang and a bright flash, along with the smell of burned plastic at the Ethernet socket side. 

This is a very dangerous thing for one to do and not a very convenient or an effective way for taking down the whole computer infrastructure. The whole point is to manage to "fry" all the devices behind the network switch!!! (..even after the network switch is "toasted", and the circuits are burned). Also, without exposing ourselves to any danger, as it would have happen if someone have used the cable mentioned earlier on. 

Monday, 21 September 2015

Skype is down!

Skype seems to be having technical difficulties! Most users can login but they appear offline. Skype said that it is still possible to chat in most occasions but not possible to receive or make calls. It seems though that the web.skype.com is working! Also, Skype for business seems to be working without issues. 
According to the Down Detector website the service appears to be out in a number of different countries worldwide. Maybe it is related to a major AWS outage which knocked Amazon, Netflix, Tinder and IMDbThe official twitter account of Skype (@Skype) posted the following message: 

"We are working to fix an issue which is preventing some users from logging in & using Skype. We apologize for any inconvenience."

Even thought this message was posted about an hour ago the Skype Support team (@SkypeSupport) posted a message four hours ago about the issue. More specifically, the message was saying that "We are aware of an issue affecting Skype status at the moment, and are working on a quick fix: sk.ype.ms/1KuQTL".
The URL sk.ype.ms/1KuQTL takes you to the skype.com domain where you can read more about the issue. This is what has been posted about the issue: 

We have detected an issue that is affecting Skype in a number of ways. 

If you're signed in to Skype, you will not be able to change your status and your contacts will all show as offline even if they are online. As a result, you won’t be able to start Skype calls to them.. 

A small number of messages to group chats are not being delivered, but in most cases you can still instant message your contacts.. 

If you aren’t signed in to Skype, you may be experiencing difficulty when attempting to sign in. Any changes to your Skype account such as your Credit balance or your profile details might take a little while to be displayed.. 

You may also have difficulty loading web pages on the Skype Community. For that reason, please check back here for future updates.. 

We're doing everything we can to fix this issue and hope to have another update for you soon. Thank you for your patience as we work to get this incident resolved.

Wednesday, 2 September 2015

Registering a .dll under Windows (solutions for 64-bit / 32-bit compatibility issues)

If you find yourself missing a .dll under the latest versions of Windows, you will have to download the missing DLL and register it in order to make it work. Also, due to the the 32-bit and 64-bit versions of Windows, you might end up with errors which you need to troubleshoot further. In this blog-post I am trying to give you a couple of hints on how to solve these compatibility issues when registering a .dll (32-bit/64-bit).