Security Corner


May 18, 2008  6:39 PM

Are You a Hacker Target?

Ken Harthun Ken Harthun Profile: Ken Harthun

Aside from those unenlightened, naive souls who invite every hacker, phisher and Nigerian scammer on the planet into their computers how many people actually fall victim to hackers? I’m talking about people who take reasonable precautions, like installing a NAT router, running a personal firewall (not Windows’ firewall) and anti-virus software. I ask this question because for some months now, I’ve been running half naked behind my hardware firewall: no anti-virus, no software firewall, just a hosts file to block known bad sites (I do update it frequently). I use both IE and Firefox for web surfing.

I haven’t been hacked, nor have I been infected by any malware. In my entire history of computing (since 1974), I’ve never been plagued by a virus or worm. I guarantee you that my PCs are not part of any botnet. No one has ever tried to run a DDOS attack on me. It’s not that I’m invisible–Google my name and you’ll get several thousand hits (some of those aren’t me; apparently more than one Ken Harthun out there). I have a couple of different web sites in plain view, too.

Am I immune to attack or just lucky? Or is it that by applying the various security tips I give you here (yes, I do the same things I tell you to do) , I’m out smarting the hackers so they can’t figure out how to get me? Food for thought. Your comments are welcome.

May 17, 2008  3:08 PM

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, free sandbox program for Windows–the one I use for secure surfing and testing– is Sandboxie. It runs only on Windows and is Vista-compatible. 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). You might want to check out the secure browsing applicance provided for VMware Player.

Security Maxim #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.


May 11, 2008  2:07 PM

No-Hassle Way to Kill ActiveX Controls

Ken Harthun Ken Harthun Profile: Ken Harthun

ActiveX has always been a weak point in IE. The majority of browser plug-in vulnerabilities are ActiveX based. Microsoft realizes this and has a method to disable certain problematic ActiveX controls. But Microsoft’s method involves setting the kill bit by editing the registry and in order to discover the CLSID (Class ID) of the control you want to disable, you may have to uninstall others. In short, it’s a messy way to do things.

Errata Security to the rescue. They’ve created AxBan, a free tool to set the kill bit on known bad ActiveX controls. Errata promises that they’ll “be updating it as needed with new CLSIDs on an as needed basis.” AxBan is a single, small (45.5 KB), standalone executable that contains a list of known dangerous ActiveX controls. It highlights in red any you have installed on your system and gives you a button to set the kill bit. Be careful, though–there isn’t an “undo” button. Once you set the kill bit, if you find you’ve made a mistake, you’ll have to edit the registry to unset it.

Nevertheless, it’s a handy tool to have in your security arsenal


May 11, 2008  1:13 PM

Windows XP SP3 Offers Enhanced Reliability and Security, But Not IE7

Ken Harthun Ken Harthun Profile: Ken Harthun

The long-awaited Windows XP Service Pack 3 became available as an Express Update May 6, 2008 on Windows Update, and offers enhanced reliability and security through a few new features: Network Access Protection (NAP), designed to work with Windows Server 2008; a product key-less install option; a Kernel Mode cryptographics module, and; a “black hole” router detection algorithm.

One puzzling thing, however, is that SP3 doesn’t include the more secure IE7–it ships with a fully-patched IE6 instead. As I found out, having applied SP3 to my systems, all of which are running IE7, this isn’t a problem; systems won’t be rolled back to IE6. Here’s an excerpt from the IE Blog:

XPSP3 will continue to ship with IE6 and contains a roll-up of the latest security updates for IE6. If you are still running Internet Explorer 6, then XPSP3 will be offered to you via Windows Update as a high priority update. You can safely install XPSP3 and will have an updated version of IE6 with all your personal preferences, such as home pages and favorites, still intact.

If you are currently running IE7 on XPSP2, Windows Update will offer you XPSP3 as a high priority update. If you choose to install XPSP3, Internet Explorer 7 will remain on your system after the install is complete.

If you’re still running IE6, you really should upgrade to IE7. Along with SP3, that will make your XP system as secure as it can be at this time.


May 1, 2008  1:16 AM

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. I’ll cover that in a future article. For now, I leave you with Maxim #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.


April 27, 2008  4:29 PM

Your Wallet is the Best Password Manager

Ken Harthun Ken Harthun Profile: Ken Harthun

Although I use them for sites that don’t require much security, password managers are something I generally stay away from. Why? Because they store the information on my hard drive or a website, both of which could be compromised by a determined hacker. Even a relatively unsophisticated hacker could exploit an unpatched vulnerability leaving my passwords open to inspection. My personal security policy is to make it as hard as possible for someone to get to my passwords.

I write them down and keep them in my wallet.

Yes, that is the most secure “password manager” there is. No one can get to your wallet from the Internet or your PC. Passwords written on a piece of paper and stored in your wallet are nearly impossible to compromise–someone would have to steal your wallet (or you’d have to lose it) to get at them. How likely is that? I’m 55 years old and have never lost my wallet or had one stolen. Just be sure not to write down your username with the passwords.


April 27, 2008  4:02 PM

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 online 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 Maxim #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.


April 17, 2008  7:05 PM

Top Five Personal Firewalls

Ken Harthun Ken Harthun Profile: Ken Harthun

How well does your personal firewall protect you? GRC’s Leak Test, PCFlank, and Bob Sundling’s TooLeaky all provide a quick way to check your personal firewall to see if it effectively blocks outbound connections. But if you really want to know how well your firewall protects you against a whole host of known attacks, check out Matousec’s Firewall Challenge website. Here are the top five based on Matousec’s extensive testing:

  1. Comodo Firewall Pro 3.0.21.329 (Free)
  2. Online Armor Personal Firewall 2.1.0.119 ($40, Free version available)
  3. ProSecurity 1.43 ($30 single PC home user, $40 household)
  4. Outpost Firewall Pro 2008 6.0.2302.264.0490 ($40/year for 3 home PCs)
  5. Kaspersky Internet Security 7.0.1.325 ($80/year for 3 PCs)

The top two, Comodo and Online Armor, scored 100% on the tests. I’m using Comodo from now on.


April 15, 2008  1:45 PM

Tighten Security With Your Hosts File

Ken Harthun Ken Harthun Profile: Ken Harthun

Using a HOSTS file to block access to malicious or unwanted web sites is an old trick and it’s excellent protection against malware. I’ve been using the mvps.org hosts file for about five years, and I have never been infected with any malware, despite, for testing purposes, intentionally visiting sites known to host it. The thing just works. It’s a great way to add an additional layer of security to your machine. You’ll also notice that many of those annoying ads no longer display in your browser.

Today, I found a cool utility that will let you download, install, and update your HOSTS file directly from the mvps.org site: Hosts File Updater, a freeware program by FaltronSoft. This single 16K executable checks the mvps.org site for a new version of the HOSTS file. If it finds one, it asks you if you want to update. Give your permission and the program backs up your existing HOSTS file and downloads and installs the new one. It also automatically sets the file to read-only, a nice feature.


April 9, 2008  9:11 PM

How to Prevent DNS Rebinding Attacks

Ken Harthun Ken Harthun Profile: Ken Harthun

There’s nothing new about the DNS rebinding attack, but it’s in the news again. Dan Kaminsky, Director of Penetration Testing for IOActive has shown a video of the attack in action at the RSA 2008 Conference. I first addressed this problem more than a year ago in a Lockergnome posting, and just recently in this Security Corner article. Both of those articles say the same thing: Change the default password on routers, switches, and any other configurable device on your network.

There’s another thing you can do: Use OpenDNS; they block known phishing and malware-infested sites, thereby making your web surfing more secure. They also just released a nifty tool called FixMyLinksys that makes it easy for anyone to change the default password and enable OpenDNS. An article at DarkReading.com had this to say about OpenDNS:

…“This will stop all the automated attacks that Dan is showing at the RSA conference today. It’s easy and is done over the Web,” says David Ulevitch, CEO of OpenDNS.

OpenDNS also launched a new type of DNS filter today that protects users from a DNS response from a malicious server. “In short, a DNS response from a malicious server that resolves to a host inside your network would get blocked,” Ulevitch says.

I’ve been using OpenDNS for some time; I’m glad to see they’ve addressed this issue directly.


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