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Tag Archives: Cryptographic protocols

Three Resolutions For Mac OS X Users

In 2011, we saw a large increase in web site exploits that exposed private user data as well as a breakdown in the trust of SSL (for various reasons) and the introduction of real malware on to the OS X scene. If there were just three things I could ask Mac users to do in 2012 to help protect themselves (‘cuz if your a Windows user it’s been game-over for years for you already) these are what they would be.

Secure & Diversify Your Web Credentials

Just like companies have lost paper files—and then laptops—containing private data, web sites have and will continue to leak your information like a sieve. While you should choose carefully which ones you let have very sensitive data (like credit card numbers, government id numbers and health information), you really do need to ensure that you at least use different and “strong” passwords at each site you have an account at to avoid having hackers replay your credentials at other sites.

The easiest way to do this is to use a utility like 1Password (@1Password & usually $50 but is on sale for $30 for a short time) by AgileBits which works with practically every browser and will let you create and use diverse passwords at the click of a button. It even works on your mobile device, so you don’t have to worry about remembering the (necessarily) ugly passwords they end up creating. You can even use 1Password to store secure notes to yourself (say, in the event you need to use complex credentials on systems you cannot install 1Password).

By using 1Password, you will avoid being the in the 60-70% of users who have their credentials stolen and have to worry or scramble because they used the same ones on an array of popular web sites. Windows users can also take advantage of this tool (and there’s a bundle price if you need it for both platforms).

You can do this without 1Password (e.g. keep a text file or spreadsheet in a secure disk image), but the ease of use is worth the price of 1Password. If you do decide to use a more manual approach, generating secure passwords with tools like this one will also help you be a bit more secure than your brain’s “random” sequence generator.

Know What’s Going On With Your System

While the Mac App Store can help ensure you aren’t loading “bad apps” onto your system, the advent of web-born malware for the Mac was seen for real this year and 2012 may prove to be the year we see the Mac becoming more of a target. There’s no guarantee that Mac App Store apps are non-malicious and you really have no idea what the ones you download from third-party sites contain, even if they do the task you want them to. Some apps that you “know” you trust may be sending out “phone home” signals or other non-user-initiated or informed-of Internet communications with unknown payloads.

This is where a cool little utility called Little Snitch (@littlesnitch and $30) by Objective Development can really help open your eyes as to what applications and processes (programs you may not be able to “see” easily without tools like the Mac Activity Monitor app) are trying to do on your network. Their own information page says it better then I could paraphrase:

Little Snitch informs you whenever a program attempts to establish an outgoing Internet connection. You can then choose to allow or deny this connection, or define a rule how to handle similar, future connection attempts. This reliably prevents private data from being sent out without your knowledge. Little Snitch runs inconspicuously in the background and it can also detect network related activity of viruses, trojans and other malware.

Again, you could monitor your Mac firewall logs by hand with the OS X Console application and tweak your own firewall rules, but Little Snitch won’t forget to watch out for you.

Secure Your Public & Untrusted WiFi Connections

While Facebook, Twitter, Gmail and other sites have SSL (https) options (some using it by default), you really need to take control of your own transmission security when not on networks you trust. Why? Well one example is that you may be at a restaurant (as I was with my kids in November) where they terminate all SSL sessions at their border gateway (meaning they could read all the data that should have been encrypted). You also cannot be sure when Facebook is going to mindlessly toggle their SSL settings or when a Facebook application causes the SSL settings to be disabled. Even though SSL is relied upon by pretty much everyone to “just work”, it’s not a given or a panacea.

When on unfamiliar, public or other untrusted networks, it’s truly necessary to take control of the encryption as best as you can and use some type of Virtual Private Network : VPN : setup. While running your own is the only real way to know what’s happening at the VPN termination point, there are reputable services out there who can provide security and that you should be able to trust (at least better than SSL in a Starbucks). One of them—and I believe the most user-friendly one—is Cloak (@getcloak and FREE to $8-$15/month) by Bourgeois Bits.

Once installed, Cloak will detect when you’re on a public WiFi connection and automatically kick in a VPN session. You can start up a VPN session at any time with a single click in the OS X menu bar and also define more granular rules (if you want to). With Cloak, you have no excuse to not take an added measure of security when you’re out and about with your Mac.

You could do this for free (provided you trust your home Internet provider) with many modern routers or even a simple Linux/BSD or OS X box providing VPN services, but it would still not be as simple as using Cloak.

With these three simple steps/apps (less than $100), you will be far less at risk than you (probably) currently are as you run naked & blind across the internet with your password stapled to your forehead.

If you have any suggestions for similar/competing tools or have additional resolutions you think would be helpful to Mac users (or any computer user), drop a note in the comments.

WEIS 2011 :: Session 2 :: Identity :: The Inconvenient Truth About Web Certificates

Nevena Vratonjic
Julien Freudiger
Vincent Bindschaedler
Jeane-Pierre Hubaux

Presentation [PDF]

Twitter transcript

#weis2011 Overview of basic ssl/tls/https concepts. Asking: how prevalent is https, what are problems with https?

#weis2011 Out of their large sample, only 1/3 (34.7%) have support for https, login is worse! only 22.6% < #data!

#weis2011 (me) just like Microsoft for patches/vulns, everyone uses Bank of America for https & identity examples. #sigh

#weis2011 More Certificates 101, but a good venn diagram explaining what authentication success looks like w/%ages. rly good visualization.

#weis2011 domain mismatch accounts for over 80% of certificate authentication failures. why? improper reuse. it has a simple solution (SNI)

#weis2011 the team did a very thorough analysis that puts data behind what most folks have probably assumed. #dataisspiffy

#weis2011 We've created a real mess for users with certs. EV certs help, but are expensive and not pervasive (***6%***!)

#weis2011 economics don't back good cert issuance practices; 0 liability on issuers; too many subcontractors; we trained users to click "OK"

#weis2011 great slide on CA success rates (hint: godaddy is #1) #sadtrombone

#weis2011 sample: 1 million web sites; less than 6% do SSL/TLS right. cheap certs == cheap "security"; policies need to change incentives

#weis2011 URL for the data is in the last slide. first question is challenging the approach for the analysis and went on for a while

Herding [Fire]sheep

By now, many non-IT and non-Security folk have heard of Firesheep, a tool written by @codebutler which allows anyone using Firefox on unprotected networks to capture and hjijack active sessions to popular social media sites (and other web sites). The sidebar/extension puts an attactive and easy-to-understand GUI over a process that “real” security people have been using for as long as there has been http-based sessions.

I’ve been using Firesheep quite a bit in non-echo-chamber demos to help illustrate some of the core issues facing enterprises and individual users. A big question that comes out of each demo is “what can I do to safeguard my access to Facebook?”. I provide quick guidance on-the-spot to interested individuals and wanted to share what I communicate to them here both to help a broader audience and get feedback on other steps users can take to safeguard their connections.

General Guidance

The first action I tell users to take is an anti-action: if at all possible, never use free/unsecured Wi-Fi connections. While there are ways of grabbing sessions and other data on wired or secure Wi-Fi networks, the means to do so are beyond the capabilities of most Firesheep users. The danger is still present and you should always consider how much you trust the network you are on when accessing anything on the Internet, but the risk is greatly diminished.

If users are unable or unwilling to follow that first action (and even if they do avoid insecure networks) I then instruct them to ensure that all services they access always use “https“ (SSL/TLS) which encrypts the communication and prevents tools like Firesheep from working. It still – much like the first action – doesn’t stop determined & skilled attackers.

I then caution users on smartphones and tablets to also make sure any applications they use also communicate over SSL. This is far too easy to overlook and can leak data just as easily as a web browser. Tablet & smartphone users can also switch to only using 3G connections to make it that much more difficut for otherrs to eavesdrop.

Finally, I suggest using a virtual private networking (VPN) service such as PureVPN to secure all their connections – not just browser sessions – on public networks (secured or otherwise). SSL/TLS connections are potentially susceptible to what is called a man-in-the-middle (MITM) attack [SANS Reading Room (PDF)] and one way to mitigate that threat is to use a VPN to secure all network communication using a more robust/holistic solution. PureVPN (and other, similar good services) are not free, but $5.00-10.00USD per month is not much to pay for personal data security on-the-go.

The Elephant In The Room

For some reason, even with that general guidance, the whole concept of someone hijacking their Facebook account really scares folks and many end up asking specific question on ensuring their Facebook access is protected. This usually involves walking them through how to check to see if SSL is enabled by Facebook’s service and also how to monitor access to their Facebook account.

Unsurprisingly, Facebook does not make setting SSL as a default an easy task. It’s unintuitively not under any “privacy” settings. Instead, you need to navigate down to account settings and poke around to get to the right areas. The screen captures below show the navigation sequence. You’ll notice that this account does not have security enabled since it’s the one I use for demos (I do not have a personal Facebook account).

Getting to Facebook Account Settings

Location of Facebook Account Security Settings

Facebook SSL Settings

You’ll also notice that you can have Facebook send you an e-mail when there is an access to your account from an unknown device and also review recent activity on your account. This gives you the ability to be in control as much or as little as you desire.

Homeward Bound

I usually close with guidance on securing your home Wi-Fi network. Many users still have an aging 802.11b/g router that barely does wired-equivalent-privacy (WEP) security. Even newer Wi-Fi equipment with Wi-Fi Protected Access (WPA/WPA2) may not be enough as you or someone else in your house most likely handout the access password to any guest you allow in the residence. Any malware on their systems now has the potential to infect other systems on your network and you have also given the keys to your local security to someone you may not fully trust. Many of the newest Wi-Fi access points – such as Apple AirPort Extremes and Netgear N[3|6]00s – provide for the ability to setup both a protected internal network and as open of a guest network as you want. I still suggest ensuring that the guest network be secured as you may be liable for any actions taken from your network (protected or otherwise).

Highway Safety

Being safe[r] on the Internet is much lke being safe[r] when driving a car. You need to make sure the fluids are at the right levels, that the tire pressure is sufficient for the driving conditions and that you wear your seatbelt before leaving the driveway. If you don’t regularly perform those tasks you run the risk of significant problems out on the road. You need to get in the habit of doing similar checks when navigating in potentially dangerous network territory as well. It doesn’t help that Facebook cares not a whit about your privacy or security and will seemingly randomly change your settings if it benefits them (or if they are just their usual incompetent selves). Want proof? You have to be diligent in the maintenance of all Internet security settings to ensure your consistent, personal online safety.