Taking A Work Notebook Home

A common scenario is when someone takes home a notebook from work. The intention is to do work from home for whatever reason.

Notebook - typingThis could be a serious security risk. Most companies have gone to a lot of trouble to secure their office networks (for example by installing and managing firewalls; though a firewall is not enough to secure a network). In fact some companies have an entire department dedicated to maintaining network security. However most homes don’t have managed firewalls or any of the other network security systems or resources that companies often use. This effectively makes a home network less secure.

The risk is having an outsider gain access to the contents of the notebook. This could be achieved in a number of ways including having a trojan on another PC in the house. The possible damage to businesses can be huge, depending on the importance of the data on the notebook, or the importance of the work being done from home.

Some misconceptions need to be explained:

  • All firewalls are the same – this is not true. There are different types of firewalls making some more secure than others. They also need to be patched when the vendor discovers a vulnerability. Some home routers even claim to have firewalls when they don’t (they claim that a NAT feature is effectively a firewall – it isn’t). SPI firewalls are good (Stateful Packet Inspection)
  • No one would be interested in hacking into your home network. The internet doesn’t discriminate, every device connected to the internet is at as much risk as every other device

It’s not all bad news though. There are things you can do to protect yourself and your employer.

  • The laptop should have an antivirus program installed. It needs to be up to date.
  • The laptop would ideally have a “personal firewall” installed. Windows Firewall is not good enough. You need something that not only stops other programs getting into the notebook, it needs to stop unknown programs already on the notebook from getting out to the internet.
  • The home router should have its own firewall, or you could use a dedicated firewall device. Ideally the firewall would filter out traffic coming from or going to known sources of malware but this isn’t going to happen at home, it requires a fair bit of maintenance (i.e. it’s expensive)
  • Encrypt the hard drive in the notebook. This can protect you if you lose the notebook or it gets stolen (and statistics show this happens often). Whole disk encryption costs money and slows down the notebook a bit but it’s very important.
  • Don’t carry all your files on the notebook. Don’t keep all your emails, or your entire client list, etc. Only copy the data you need to get the job done and limit the risk.
  • A VPN to your office network can help.
  • Don’t connect your notebook to the internet. These days almost everyone needs the internet to do work so this idea might not be very practical
  • Don’t use someone else’s wireless network. Not only is this illegal in many countries, you would be sending all your data through a stranger’s network. It’s technically possible for someone to intercept that data, even to manipulate it.
  • If you use wireless at all make sure it uses a strong security protocol (WPA or WPA2)

A note about VPNs:

VPN stands for Virtual Private Network. It’s a piece of technology that can be used to join an office network to a home network. Servers and PCs on the networks would behave as if they were sitting in the same location, ignoring the fact there’s some distance inbetween, and ignoring the fact it’s really travelling across the Internet.

A VPN isn’t the be all and end all of security, it’s only a technical solution to a technical problem. You still need firewalls, virus scanners, and a little bit of tech support.

They can be setup to route all traffic to your office network and then you would trust your office network to filter the traffic for you. This is generally good. There are some caveats:

  •  Activities like internet browsing are slowed down
  • Your office network may keep a log of what websites you view from home, when you’re connected to the VPN
  • You’re trusting your office’s IT staff not to hack into your home network (it’s technically easier when you establish a VPN)
  • It costs your employer money to setup and manage a VPN
  • If you have an unreliable internet connection at home it’ll disrupt your work.

Above all find out what your company’s IT policies are and follow them as best you can. If they don’t have one then now’s a good time to suggest one. Working from home doesn’t have to be risky.

Wireless Keyboards are easily hacked

Wireless keyboards can be intercepted, very easily. This is something you should be aware of not only when purchasing new equipment but when using someone else’s computer. There’s no real defence against it either, other than using a wired keyboard.

Before I explain the risks let me point out which keyboards it does and doesn’t affect:

  • All keyboards using a 27MHz transmitter are at risk (which includes most of them)
  • Keyboards that advertise "wireless encryption" or "secure" features are also at risk
  • Bluetooth keyboards are safer (though these are generally more expensive)

typewriter The risks of such an "attack" should be obvious – other people within range could be recording every keystroke. This includes the address of websites you go to, usernames, passwords, the contents of emails, chat conversations, etc.

In a business environment this would be a critical breach of security. Giving away passwords, trade secrets, and other sensitive information is quite serious, and in a lot of cases criminally irresponsible. Wireless keyboards that fall into the "at risk" categories above should be banned.

At home the risks are just as serious. Anyone using a home computer to do internet banking should immediately recognise the dangers of giving away too much information (i.e. finding a large amount of money removed from your bank account). Again, either use a wired keyboard at home, a Bluetooth wireless keyboard (expensive), or limit the keyboard & computer’s use to trivial tasks such as gaming.

How does the attack work?

Well, it seems there are only 256 possible encryption codes, so hackers have cleverly written software that tries them all within seconds. Then there are other tricks they use to break the encryption that some keyboards use (for the IT savvy reader, it’s an XOR protocol).

So it takes about 20 to 50 keystrokes before enough information can be gathered to break the encryption.

How close does one need to be to "sniff" wireless keyboard signals? Usually it’s 4-8 feet, or 1-3 metres. But with more powerful aerials this can be extended much further (hundreds of metres).

Also keep in mind that Bluetooth generally isn’t a very security protocol. It’s only considered safer because of how easy it now is to hack normal wireless keyboards. But you shouldn’t use it to keep million dollar secrets.

There’s a video here demonstrating how it works (warning, it’s geeky and technical): Wireless keyboard hacking.

So go back to wired keyboards, they not only more reliable and more secure, they don’t have batteries that need replacing or recharging.

Chinese CyberSpying

Security Gate British businesses are being warned about Chinese industrial espionage aimed at retrieving financially sensitive data. In particular, at least 1000 businesses have been warned that they’ve potentially been targeted to obtain data on their trading with Chinese companies, in an attempt for the Chinese parties to negotiate higher prices in their business dealings. There’s an article here with the full story.

This post is aimed at businesses, whether large or small. Online espionage, or cyber spying, is a real threat. It doesn’t necessarily need to come from China either, the technology and skills exist in just about every city and country that’s connected to the internet.

Everyone needs to secure both their networks and the computers with it. The old belief that a firewall is enough has always been false, even more so now that data threats can come from so many levels (see the SANS document that was mentioned here earlier). It’s everyone’s responsibility to do everything within their power to increase security. The threats are out there, large amounts of (your) money are stake, and there’s always something you can do.

So now is a good time to review your network security and to improve it.

Top 20 Internet Security Risks

SANS is an organisation that does a lot of security research as well as other things, and they have a good reputation for their work. They’ve just published a report showing the top 20 internet security risks. They point out that social engineering is one of the biggest risks at the moment. Social engineering is the term used to describe how people effectively trick (or otherwise convince) others to provide sensitive details.

There’s a lot of detail in this report and it’s well worth reading. Below are a few bits of information from the report and it’s just not possible to summarise it all here. Have a read through it if you have time.

  • Web applications are vulnerable to being hacked and information misused or stolen.
  • People can be manipulated
  • The following applications are the most vulnerable:
    • Web Browsers
    • Office Software
    • Email Clients
    • Media Players
  • Unencrypted laptops are a risk to losing large amounts of data
  • Instant messaging and peer-to-peer programs are a risk to businesses

The full report is here. It’s long and very detailed, and well worth your time in reading it.

Bluetooth Headsets

Most Bluetooth headsets are not secure. I encourage everyone to watch the video linked below to see how easy they are to hack.

In this demonstration by Joshua Wright he connects to a stranger’s bluetooth headset and is able to eavesdrop on the random stranger. He also briefly shows how audio can also be sent to the headset. Anyone with a Bluetooth headset that’s currently on is at risk of something like this. The biggest part of the risk is that almost all Bluetooth headsets use a default PIN (usually 0000).

Watch the video here.

Suspicious Websites

It's a trapWith apologies to all those who conduct legitimate activties on the following sites I’d like to warn you on the current trend of malicious sites.

At the moment a lot of sites hosted on Geocities contain various bits of malware. So if you see a link anywhere (in an email, in a chat window, on another web page) that begins with geocities.com be very suspicious.

And secondly there’s been so much malware coming from Chinese web sites. So be cautious of any link that has .cn in the address.

A plug-in must be installed

In order to view the photos a plug-in must be installed.”

Binoculars These dreadful words have been appearing in some spam emails, in Dutch. And on top of that the emails, at first glance, appear to be a legitimate news article. Interested readers might be tempted to click on the link, install the suggested plug-in, and hope to view photos of whatever the email is about.

You should never install anything an unsolicited email tells you to. You shouldn’t have to install anything to view photos. These particular spam emails will provide a link to a file called iPIX-install.exewhich is in fact a trojan that spies on your computer.

Another point worth mentioning is that spam and malicious emails are now being sent in languages other than English in the hope of catching out people who live in non English speaking countries (by trying to win their trust).

Collecting Passwords

This statement from Bruce Schneier is interesting,

How to harvest passwords: Just put up a password strength meter and encourage people to submit their passwords for testing. You might want to collect names and e-mail addresses, too.

It points out how easy it is for someone to collect passwords. A couple of human weaknesses are at play here:

  • People tend to trust programs they come across on the internet (and websites and services) . More-so if it looks new and shiny.
  • People tend to use the same password on multiple sites.

The internet’s a very dynamic environment, and with the rise of Web 2.0 we have lots of interesting new sites appearing daily. Most of them ask us to register, to provide a username and a password.

And behind every interesting new site are people (the programmers). Most of the time their intentions are honourable, providing an application online (and often for free). But what if a website’s intentions are more devious? What happens when you register an account and type in a (new) password? Usually it gets encrypted and stored in a database. It would be a simple task for the programmer to change the code and get it to store your password in some other way. And if people continue to use one or two password for all sites this information becomes a little more valuable.

In other words it would be easy for the programmer of any new and interesting web site to collect user names, email addresses, and your favourite passwords.

So always be cautious of where you type your password, it can be a valuable thing.

Don’t always trust websites. There are a few exceptions – Google for example does an excellent job with their users’ security.

And whenever possible don’t reuse important passwords on websites you don’t trust.

Keep critical software up to date

Some programs you use are critical to the safe use of your computer, and it’s important to keep these patched.

In this article critical software is the collection of programs (both visible and those that run in the background) that transport information from a web server to your screen. It’s the chain of data flow that you use the most often when using the internet.

You have your operating system (e.g. Windows, MacOS, Linux), a web browser, and a stack of drivers that basically make the internet work for you. This is a simplified model, most people’s computers will be unique and full of all sorts of programs.

Because information is flowing along this chain of programs, data being handed off from the operating system to the web browser, every link in the chain is critical. And like the old mantra, the price of security is eternal vigilance. In this case we’re looking at the eternal task of patching your software.

Patches are released by software vendors, whether it’s a free open source program or from a commercial software company. Patches are written because the programmers are always fixing bugs, in particular they’re always fixing security vulnerabilities as they are discovered. It’s a way of strengthening each of the links in your data chain.

The point of this article is that you should always update the following:

  • Patch your operating system (Windows, Mac OS, Linux, etc). Yes there’s a risk in being the first to install a patch, it might break something. Large companies have long complicated procedures to test patches before installing them. Small companies and home users need to take the risk and apply the patch blindly, trusting the vendor. It’s a choice between having the most secure computer possible or waiting to see if a patch is released by mistake. My advice is to take the secure option and make regular backups of all your data (backups would be a good topic for a future article). Most operating systems these days have automated patching systems in place making this simple and often a transparent process.
  • Patch your web browser. All web browsers need to be patched – Microsoft Internet Explorer (IE), FireFox, Opera, Safari, etc. Apply patches as soon as they’re released. Today a web browser is the most vulnerable program on a computer, it gets used to run code that other people write. Code that comes from all corners of the world and is almost always not certified in any way and there’s almost no way of trusting the code. Your web browser will execute it blindly, trusting that it’s safe and you trust that all other programs on your computer (including the operating system) will handle the attacks in a graceful way. Web browsers will be attacked, this is almost a certainty these days. So you need to very latest version that hopefully has had every known vulnerability fixed.
  • Patch your antivirus software. This is often automatic, and it’s often a paid service. Antivirus companies spend a lot of time and money keeping their tools up to date and it’s in your best interest to use their technology. Consider it a good investment, it could cost you thousands of dollars if your system is compromised.
  • Sometimes routers will have to be patched as well. This is a little more advanced and you should only do it if you’re comfortable working with your router.
  • Personal firewalls should also be patched. If your antivirus software includes a [personal] firewall then it’ll be patched automatically, otherwise it’s a separate process.

Chain and padlockAll software that uses the internet in any way, including the various video and music players, needs to be kept up to date. Web browsers and operating systems are the most critical and should be patched the most often. The time and effort you spend is the price you pay for having a safe computer.