Security Corner

December 8, 2009  8:53 PM

Golden Rule #10: Store Your Backups Securely

Ken Harthun Ken Harthun Profile: Ken Harthun

A friend of mine once told me, “I love your computer security maxims, but there’s one thing I don’t have anything to worry about–I keep all of my passwords stored on an encrypted thumb drive.”

“Well, that’s a good thing,” I said. “Where do you keep your backups?”

“On my external USB drive.”

“That’s encrypted, right?” I asked.

He blinked and looked away. “No.”

Doh! If a cracker is able to access his PC and that drive is connected and turned on, my friend could be toast. If someone breaks into his house and steals the drive, my friend’s identity could be stolen. Depending on what is actually stored on the hard drive, full backups can contain lots of personal information–information that is much more valuable than mere passwords. Think about it: if you have the user’s name, address, SSN, pet photos, you-name-it, you’re in Fat City; you can easily assume the identity and recover usernames and passwords.

Few people encrypt their data, much less their backups. They should, but they don’t. Some backup programs allow you to make encrypted backups. If this option is available take advantage of it. The most secure plan would be to both encrypt your data and encrypt the backup for a double layer of protection. Then, take the backup media offline and store it in a secure place.

And that is Golden Rule #10: When using external removable media for backups, either encrypt the backup files or make sure the media is taken offline after the backup has been completed.

December 5, 2009  6:20 PM

Golden Rule #9: Two Ways to Operate Securely on the Web

Ken Harthun Ken Harthun Profile: Ken Harthun

If you’ve done any coding at all, you probably have a good idea why software developers often run their untested code in a protected environment–a sandbox. If the software misbehaves, all you have to do is shut down the sandbox and everything returns to normal, no harm done.

A sandbox is also a great way to prevent viruses and other malware from infecting your machine while browsing the web. Confine your browser to its own little box and if any malicious software tries to run, it can’t get to your system, it stays within in the box’s boundaries. Kill the box and you kill the malware. The top, sandbox program for Windows–the one I use for secure surfing and testing– is Sandboxie. It runs only on Windows. Run Internet Explorer, Firefox, or any other program under Sandboxie and you should be safe.

Flash Update: Seems CheckPoint agrees and has released a product of its own. Check out this article from Dark Reading.

You can also operate securely from inside a virtual machine. This is different from a sandbox in that you actually run an entire operating system, rather than a single program. Many people, this Geek included, use virtual machines to run alternative operating systems like Linux. In a virtual machine, you can do everything you do on a real machine and like the sandbox, if things go wrong, your computer won’t be harmed. A big advantage of the virtual machine over a sandbox is that you can examine the actual behavior of malware and any damage to the OS. Microsoft provides the free Virtual PC and VMware provides its free VMware Player and VMware Server. For the Mac, there’s Parallels (not free).

Golden Rule #9: When surfing the web, testing unknown programs, or engaging in other activities with the potential to harm your computer, use a sandbox or virtual machine to protect your base system from harm.

December 5, 2009  5:35 PM

Golden Rule #8: Does Encryption Have You Complacent About Physical Security?

Ken Harthun Ken Harthun Profile: Ken Harthun

There’s no question that data security is senior to physical security. The real value in a stolen laptop or PC isn’t in the hardware, it’s in the data. Sure, some druggie might steal your laptop and sell it for a fix, but the real danger lies in the thief who knows the value of the files that are stored on it. If it’s a personal laptop, the passwords to your online banking site, credit card numbers, Social Security number–probably everything about your identity–may be stored on it. If it’s a corporate laptop, depending on who you work for, there could be valuable customer information complete with credit card numbers or other proprietary information that a thief or corporate spy could capitalize on.

But physical security is only slightly less important. Don’t get complacent thinking that you’re OK just because your data is secure. It’s an expensive proposition to replace that data, so you must take steps to prevent theft of your hardware.

Encrypting your data is analogous to hiding it. So hide your laptop. Chain down your PC. Make it as difficult as possible for a thief to steal it. I keep my PC in a locked room when I’m not nearby and I maintain the attitude that someone’s waiting around the next corner to steal my laptop. So, it’s always either in a secure area or with me–and I mean within a couple of feet of me. I rarely leave it in my car and if for some reason I must, I lock it up in the trunk. I never leave it overnight in the office. Out of sight, out of mind. There are other physical precautions you can take as this Security Focus article outlines.

And let’s not forget about removable and external storage devices; hide them, too. For now, I leave you with Golden Rule #8: Physical security is almost as important as data security. Make it as difficult as possible through any physical means for a thief to steal your hardware. Rules of thumb: Lock it up and lock it down; out of sight, out of mind.

November 27, 2009  6:18 PM

Golden Rule #7: If Your Laptop is Stolen, Will Your Identity be Stolen?

Ken Harthun Ken Harthun Profile: Ken Harthun

We frequently hear news of a laptop holding sensitive information having been stolen. Bad in itself, but the reports often note that the information was unencrypted. Doubly bad. The news rarely focuses on personal laptop thefts, however because there’s no news value in reporting the loss of Joe Citizen’s personal files; nothing of value there, they think. But Joe’s entire life savings may soon be wiped out if he has ever used that laptop for on-line banking or other financial transactions.

Recently, a friend of mine (who shall remain nameless for security reasons) had his laptop stolen out of his car. Fortunately, he had just purchased it and there was nothing of value on it, but there could have been–he’s an oil company executive. Modern thieves know that if they can get their hands on a computer holding sensitive information — particularly bank or credit card information — they can sell that computer for tens or hundreds of times the value of the hardware. The hardware is virtually worthless to them. From the thief’s point of view, any laptop sitting on the seat or floor of a decent car or a desktop PC in a middle class home office could belong to someone who has access to valuable information.

But, if the data is encrypted, the thief is out of luck.

I’ll cover physical security later. For now, I present Golden Rule #7: If you store sensitive information on a PC or laptop, even if it’s only personal information, encrypt the folders or drives where the information is stored and use an unguessable passphrase as the encryption key.

November 27, 2009  5:19 PM

Golden Rule #6: Turn off Message Preview in Your Email Client

Ken Harthun Ken Harthun Profile: Ken Harthun

Outlook Express Preview PaneSome of these tips may very well be “everybody knows” types of things, but I find that these are often the things that get overlooked. That’s why I’m publishing them as golden rules. Take a look at the 2008 furor surrounding the cold boot attack against disk encryption . That was an “everbody knows,” too.

I get questions all the over at Ask the Geek about using a mail client’s message preview feature. Opinions vary, of course, but for this Geek, it’s a bad idea. In order to preview a message, it has to be opened or rendered by the HTML engine. Think about how a PC can be infected by a malicious web site and you’ll immediately understand the danger: The same malicious programs can exist in scripts in HTML messages. It’s a serious security risk.

Golden Rule #6: Always disable any message preview or auto-open features in your e-mail client. View messages as text-only until you know they are safe.

November 27, 2009  5:02 PM

Golden Rule #5: If You’re not Patched, You’re a Target

Ken Harthun Ken Harthun Profile: Ken Harthun

OK. So you’ve installed a NAT router, you’ve changed the default login and passsword, and you’ve used an unguessable password. You’ve done everything right so far; however, you still may be vulnerable–in fact, you probably are, even if you keep your operating system patched. In a 2007 Lockergnome posting, I wrote:

“To say nothing of Microsoft Windows, there are few, if any, application software packages that are free of security vulnerabilities. The SANS Institute publishes its Top 20 Internet Security Attack Targets on a regular basis and Secunia currently lists 14,043 pieces of software and operating systems with vulnerabilities.”

Not surprising, Secunia reports that as of November 27, 2009 , the above number has increase by almost 13,300:

“Our database currently includes 27,298 pieces of software and operating systems.”

It probably won’t surprise you that Microsoft leads the list, but that is by no means the only source of security vulnerabilities out there. The truth is, if you’re on the ‘Net and running any unpatched software, you’re a target; I can look at my firewall logs and identify what vulnerabilities are being targeted on my machine. Many of these holes have long since been patched and there’s no excuse for your not having patched them.

So much for the bad news. The good news is that most reputable software companies, when informed of a vulnerability by security researchers, promptly issue a software patch to fix it. These are widely available to the public for free download or through update features built into the software packages. Windows and other software packages allow you to enable automatic updates (which you should do).

Golden Rule #5: A vital part of PC security is keeping up with software patches for ALL of the software on your system, not just the operating system. Where it is available, use the software’s automatic updates feature.

November 25, 2009  2:13 AM

Golden Rule #4: Can a Criminal Hacker Guess Your Password?

Ken Harthun Ken Harthun Profile: Ken Harthun

Golden Rule #3 stressed the importance of changing the default user name and passwords of all configurable network devices. That’s good advice. But a weak password, one that is easily guessable, is almost as bad as no password. Far too many people use a password that’s obvious; i.e., given some basic information about the person, a determined hacker could easily guess it without too much effort.

Two clients I have serviced, both of which generate some serious confidential data, set up initial passwords for new users in the form password.2008 or changeme. (Thankfully, I recently convinced both of these clients to implement strong password policies!) I’ve been able to use basic observation and small talk to guess users’ passwords about 20% of the time. The first thing I try is a blank password–you’d be surprised how often that works, especially for home users. Next, I’ll try the user name, the spouse’s name or “password.” I may try a couple of other things, like “123456,” “asdfjkl;” or, believe it or not, “********.” Usually, though, I just ask them for the password and they give it to me.

According to Wikepedia there are several things many people use as passwords that results in their being predictable:

Repeated research has demonstrated that around 40% of user-chosen passwords are readily guessable because of the use of these patterns:

  • blank (none)

  • the word “password”, “passcode”, “admin” and their derivates

  • the user’s name or login name

  • the name of their significant other or another relative

  • their birthplace or date of birth

  • a pet’s name

  • automobile license plate number

  • a simple modification of one of the preceding, such as suffixing a digit or reversing the order of the letters.

  • a row of letters from a standard keyboard layout (eg, the qwerty keyboardqwerty itself, asdf, or qwertyuiop)

So, if you want to protect your router and the other devices on your network, never use anything from the above list and apply Golden Rule #4: Use an unguessable, or difficult-to-guess password always.

November 25, 2009  2:04 AM

Golden Rule #3: Omit This Setup Step and Your Router Can Be Easily Compromised

Ken Harthun Ken Harthun Profile: Ken Harthun

Golden Rule #2 stressed having a NAT router–or router/firewall–between your PC and the Internet as a first line of defense. This is without question the first, most important security step, but it can be useless unless you have it properly configured; in fact, omitting one crucial first step can leave you even more vulnerable to attack that you would be without the device.

All routers come with a default user name and password, often as simple as admin/admin (when I’m faced with a router I haven’t seen before, this is the first thing I try–and it often gets me in). Default settings are a good thing because if you ever forget your password, you can reset the router and take it back to square one. However, this is also a dangerous security risk–these defaults are well known and published on the Web. A couple of years ago, for example, three of the more widely used consumer routers, Linksys, D-Link, and Netgear, were vulnerable to a JavaScript web page attack. Go to the wrong site and if you haven’t changed the default password, the attacker can change your router’s settings to send you to malicious websites. For example, you’ll think you’re looking at your bank’s login page, but it will be a fake look-alike that steals your account information as soon as you log in.

While the manufacturers try to patch such vulnerabilities, users often don’t apply the patches and even if they do, determine hackers often find other ways in. As recently as October, 2009, a blogger who stumbled across a vulnerability in more than 65,000 Time Warner Cable customer routers says the routers are still vulnerable to remote attack, despite claims by the company that it patched the routers. A report by Wired found that 45 percent of 2,729 publicly accessible Linksys routers still had a default password in place.

And that is precisely why you should put this on your list as Golden Rule #3: Always change the default user name and password of any configurable device you put on your home network.

November 24, 2009  3:44 AM

Golden Rule #2: How Not to Invite Attackers into Your PCs or Network – the First Line of Defense

Ken Harthun Ken Harthun Profile: Ken Harthun

Golden Rule #1 gives what I consider to be the most basic security maxim, one on which I base all of my security practices, so let me repeat: The best security measures are completely useless if you invite attackers into your PCs or networks.

Windows users will remember back before Windows XP Service Pack 2 was released that simply plugging your computer into your cable or DSL modem was almost certain to result in your being compromised in short order. (Who can forget the havoc that Sasser and other worms wreaked before Microsoft wised up and finally turned the firewall on by default?) Running naked with all ports open to the world is a gold-gilt invitation to every criminal and mischief maker on the Internet, and while running a software firewall is a good idea, it’s not nearly enough–crackers have known for some time how to disable the Window’s firewall.

Consider this: every IP address owned and/or issued by your Internet Service Provider, no matter who that may be, is constantly being targeted by hackers that are scanning the’Net for vulnerable systems, and worms, viruses and other malware that have already infected machines on the ‘Net. (As I write this, the IP address assigned to me by my cable Internet provider has been scanned or probed 46 times in the last hour; this goes on 24 hours a day, seven days a week.) I certainly don’t want my PC’s software firewall subjected to this kind of thing. Yet, most people, not knowing any better, plug their computer directly into the broadband modem. There is absolutely no reason to do this when there is an inexpensive, simple, yet effective first line of defense available at any big box electronics or office supply superstore–a router (Fig. 1).

Figure 1

Figure 1

Through the beauty of Network Address Translation (NAT), even the cheapest router becomes an effective hardware firewall, virtually making your PC invisible to the ‘Net. NAT Router Security Solutions by Steve Gibson of “Security Now!” explains NAT in detail. Here’s one of his illustrations from that article:

I must mention that except for one, easy configuration change that is absolutely essential, these simple devices work fine right out of the box. The average user can plug it in and not have to worry about a complicated setup process.

Golden Rule #2: A first, important step in securing your PC is to install and configure a NAT router.

November 24, 2009  3:30 AM

Golden Rule #1: Don’t Invite Attackers into Your PCs or Networks

Ken Harthun Ken Harthun Profile: Ken Harthun

Having worked in IT in various capacities since the early 1980’s, I’ve seen the need for security evolve from simple protection against viruses to the need for complex security policies designed to combat multiple attack vectors. These days, it takes constant vigilance to stay ahead of criminal hackers, to say nothing of terrorists; moreover, clueless users are often unwitting accomplices in security breaches. (See my article “Will You Be Used As a Weapon Against Your Own Country?“)

Today’s Internet is reminiscent of the Wild, Wild, West, only now it’s the Wild, Wild Web. Make a mistake, and you could be virtually dead before sundown, your identity stolen, your financial resources drained, your reputation ruined. Protecting yourself online seems like a daunting task, especially for the average home computer user; however, it’s not as hard as it seems, given some common sense and an understanding of basic security principles.

My goal for this eBook is to provide simple, sound advice and tips that will help you be more secure in your computing both at home and at the office. The first piece of advice I’ll give you is one I consider the most basic principle of computer security, the first Golden Rule of Computer Security: The best security measures are completely useless if you invite attackers into your PCs or networks.

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