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Tag Archives: Malware

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.

DNSChanger Detector

The FBI made a tool to help you determine if you were a victim of the DNSChanger malware.

If you’re like many casual Internet users, you have no idea how to get the information to plug into the input box.

Unfortunately, the security model of most modern browsers makes it impossible to easily retrieve this information. However, it is possible to grab the DNS entries if the user is willing to trust the requesting source.

To help make it easier to determine if you’re infected, I wrote DNSChanger Detector. It’s a small Java applet that requires the user to allow it to have privileged access to the DNS entries via a call to sun.net.dns.ResolverConfiguration to get the nameservers. Once it has them, there is some jQuery glue in place to let Javascript access the results.

I understand why the FBI didn’t attempt to go this route, but it will hopefully be useful to folks who don’t wish to walk their friends and family through the process.

WEIS 2011 :: Session 1 :: Attacks :: The Impact of Immediate Disclosure on Attack Diffusion & Volume

Sam Ransbotham
Sabayasachi Mitra

Presentation [PDF]

Twitter transcript

#weis2011 Does immediate disclosure of vulns affect exploitation attempts? Looking at impact on risk/diffusion/volume

#weis2011 speaker is presenting standard attack process & security processes timelines (slides will be in the blog post)

#weis2011 the fundamental question is when from the vulnerability discovery to patch development is disclosure appropriate

#weis2011 immediate disclosure places a significant amount of pressure on defenders while aiding attackers < yep. #weis2011 penalty for MSSP, IDS/IDP/malware vendors for not doing nigh daily "software updates" is huge. a very high pressure industry. #weis2011 IDS systems produce tons of records which needs to be analyzed and understood. results may or may not be actionable. #weis2011 *Tons* of neat data on analysis of NVD data. Very data rich slides (some of them). Lots of math. #good #stuff #weis2011 immediate disclosure has significant increase in acceleration of exploit devel only slight increase in penetration #weis2011 the window may open faster, but defenders are reacting really quickly. this has effect of causing attackers to stop attacks sooner #weis2011 vendors patch vulnerabilities that have been immediately disclosed faster than "traditional" ones. #weiss answer to a q: "the data does not support immediate disclosure for all vulns. no way to extrapolate that information"

“Web Development Is Dangerous”

Those were the words that greeted me within five minutes of checking out the Flask microframework for Python web applications. I feel compelled to inline those four, short paragraphs:

I’m not joking. Well, maybe a little. If you write a web application, you are probably allowing users to register and leave their data on your server. The users are entrusting you with data. And even if you are the only user that might leave data in your application, you still want that data to be stored securely.

Unfortunately, there are many ways the security of a web application can be compromised. Flask protects you against one of the most common security problems of modern web applications: cross-site scripting (XSS). Unless you deliberately mark insecure HTML as secure, Flask and the underlying Jinja2 template engine have you covered. But there are many more ways to cause security problems.

The documentation will warn you about aspects of web development that require attention to security. Some of these security concerns are far more complex than one might think, and we all sometimes underestimate the likelihood that a vulnerability will be exploited, until a clever attacker figures out a way to exploit our applications. And don’t think that your application is not important enough to attract an attacker. Depending on the kind of attack, chances are that automated bots are probing for ways to fill your database with spam, links to malicious software, and the like.

So always keep security in mind when doing web development.

Let’s look at the key take-away messages…

Data Should Be Stored Securely

Interestingly enough, this is not the default mindset of one of the more popular modern database technologies [mongoDB] (and it has plenty of company [memcached], too).

Even if your app starts out without any real sensitive data, odds are you will be storing credentials, e-mail addresses, social network handles and other bits of information that you should feel some fundamental responsibility to treat with care. There are somemcached manymysql resourcesoracle tocouchdb helpsqlite that you really have no excuse.

And, it will save you time later on when you realize you actually need to have a secure storage foundation.

Watch The Input To Your Apps

Flask protects you against one of the most common security problems of modern web applications: cross-site scripting (XSS). There are many others. If you are a programmer and have never even heard of OWASP, then you need to put down your PS3/Xbox controller and do a quick read on at least their take on the top ten web app security risks (btw: there are way more than ten, but you need to start somewhere).

The thing is, unless the halls of higher education have crumbled completely since I was in school, I distinctly remember having the concept of input validation, bounds checking, etc. being rammed into my thick skull in almost every programming class (and this was way before web apps were even contemplated). You may think you’re innovating by posting a link to your functioning rapid prototype on Hacker News, but what you’re really doing is being sloppy, lazy and irresponsible. Period.

And, while it’s fine to seek out frameworks like Flask and rely on some of their inherent protections, it does not absolve you from your responsibility to deliberately & consciously build rugged software (which doesn’t just mean “secure”).

“Don’t think that your application is not important enough to attract an attacker”

I’m not sure if any amount of verbiage will convince someone of this fact if they are determined not to believe/accept it. It’s a much larger discussion (and this is already a long post). If you are inclined to have a slightly open mind, I encourage you to read So You Think Your Website Won’t Get Hacked by Joseph Schembr. It’s really slanted towards “script-kiddies,” but should pique your interest enough to keep exploring why your hacked-up personal URL shortener might be a target.

Fin

It’s impressive that the Flask authors cover security in some way, shape or form on 21 pages in the documentation [PDF]. If you’re building or contributing to other frameworks, projects or engines (hint, hint, Node.JS devs!) I would strongly encourage you to take as much time and consideration as the Flask team did to ensure you are making it as easy as possible for your users to deploy applications as securely as possible by default.