Shellshock Vulnerability – What It Is & Recommendations

Shellshock VulnerabilityUPDATE – 9/26, 1:35 p.m. PT: Customers with WAFs (Web Application Firewalls), IPS’, and other security devices may have noticed that we have some checks already in place, with results / vulnerabilities coming out of the system. The nature of the Shellshock vulnerability requiring only a single http(s) request means that the number of attack vectors are numerous and as such we will be continuing to improve our testing methodology in the days and weeks to come. It is of the utmost importance that we reiterate the importance of checking your systems directly and patching as other services may be available such as SSH, CUPS and DHCP.

UPDATE – 9/25, 5:00 p.m. PT: The WhiteHat Research & Development team has been working hard to dissect the Shellshock issue and deploy additional checks as necessary to Sentinel.

Prior to the announcement of Shellshock, WhiteHat Sentinel Source had already been testing for applications making use of untrusted data in conjunction with the operating system’s shell interface to execute native commands and applications writing untrusted data to a system environment variable. In the Bash shell, injection into an environment variable can also lead to remote code execution. Failure to properly validate and or encode data utilized by the shell allows an attacker to execute arbitrary operating system commands. This is dangerous because environment variables can be used in other parts of the application, external process on the host, or even other applications. Many applications implicitly trust environment variables to be safe, so this data is often not checked for suspicious activity. Both of the checks in Sentinel Source are able to accurately identify the type of behavior that Shellshock is vulnerable to.

The ‘Shellshock’ exploit (CVE-2014-6271) announced yesterday is a vulnerability found in the Bash command interpreter. Bash is the shell, or command language interpreter, whose name is an acronym for the ‘Bourne-Again Shell.’ Injection vulnerabilities in web apps are a death blow: they are the one class of vulnerability that accounts for more data loss than all other vulnerabilities. The Shellshock bug is a code-injection vulnerability that allows an attacker to pass commands to Bash to execute arbitrary code. This is a critical issue for any application that evaluates user input and calls other applications via a shell. The CVE severity score for Shell Shock is 10 on a scale of 1 to 10. Given that this vulnerability is known to be ‘wormable’ 10 almost seems like it is not high enough. This issue is likely to be of greater concern than Heartbleed (which we posted about here and here) was earlier this year.

The extent to which this vulnerability affects the web is still unfolding. WhiteHat has confirmed that cgi-script based web applications may be vulnerable, especially those that call other applications via the shell. Apache servers using mod_cgi or mod_cgid are affected if CGI scripts are either written in bash, or spawn subshells. We have also observed several working pieces of exploit code in the wild that requires a minimal amount of technical expertise to execute. WhiteHat is implementing a detection for this vulnerability to identify the existence of this critical vulnerability in their web applications. At this time is highly advisable that you patch all systems running Bash. Additionally, there are several working mitigations currently available for this vulnerability:

  1. Upgrading to a new version of bash
  2. Replacing bash with an alternate shell such as zsh
  3. Limiting access to vulnerable services, or filtering inputs to vulnerable services

Editor’s note: Want to learn more about Shellshock? Register for our town hall discussion.

We will continue to provide regular updates as they become available.

Other Resources for more information on this bug as it unfolds:
GNU bash Environment Variable Processing Flaws Let Users Execute Arbitrary Code
Shellshock DHCP RCE Proof of Concept
[SECURITY] [DSA 3032-1] bash security update
Bash specially-crafted environment variables code injection attack
Bash ‘shellshock’ bug is wormable
Everything you need to know about the Shellshock Bash bug
Bash ‘shellshock’ scan of the Internet
Quick notes about the bash bug, its impact, and the fixes so far
Bash specially-crafted environment variables code injection attack
Environment Bashing

Mile-High AppSec

I just returned from AppSec USA last week in Denver. Many of you are likely familiar with this conference: it’s when our good friends over at OWASP pick a lucky city and converge on it, bringing together some of the world’s best-known application security practitioners, experts and hackers. WhiteHat Security had about 10 people floating around between sessions, booths, and several fun after-hours endeavours. As per past years, last week Denver was the place to be if you work in application security.

I had the good fortune of being a panelist in one session discussing the use of Open Source software in the Enterprise. The panel was moderated by Sonatype’s Derek E. Weeks (@weekstweets) who helped put together the Open Source Security survey we were discussing. Other panelists included Josh Corman (@joshcorman), Damon Edwards (@damonedwards), and Jeff Williams (@planetlevel), who were all fantastic contributors and really bright guys in general. We had some really interesting takeaways from our conversation which were eye-opening:

  1. Open Source Security policies are rare and when they exist, they are even more rarely followed.
  2. Most companies still rely on *manual* testing of their codebase, including the Open Source libraries.
  3. Even when manual testing occurs it tends to happen mostly in production.
  4. Nobody knows what Open Source libraries they use or where they live.
  5. Responsibility for security of Open Source libraries is very varied (IT, Compliance, Risk, Security).
  6. -10. Heartbleed sucked hard.

Here is a video of the panel.

After the panel I also got a chance to present the Top 10 Web Hacking Techniques of 2013 with my esteemed colleague Johnathan Kuskos (@johnathankuskos). For those of you who follow the WhiteHat blog, this should be old hat for you (we ran this presentation via a webinar and living blog post here earlier this year). The content is fantastic, the researchers we pay homage to are all top-notch, and the hacks this year were really creative and some went very deep into the technical nitty gritty.

If you want to see some of the AppSec talks check out the OWASP YouTube channel which they are updating daily as they process these recordings. I’m sure the Top 10 will pop up there in the next few days.

Other than talks, you can all join me in congratulating Johnathan Kuskos in winning this year’s WaspNestCTF, developed by the OWASP Boulder, Colorado chapter. Johnathan tied for first place against a team of three… all by himself. This also means he won some additional prizes for most flags captured by a single person. Congrats Kuskos!

We also took the opportunity to launch our new WhiteHat HackerKast web series while in Denver, after all it’s not often that three of us are in the same room together! You can view the first episode below. HackerKast will be a weekly conversation between three of us at WhiteHat in which we discuss the latest news that people are talking about on Twitter, latest news headlines or interesting pieces of research that we believe the industry will benefit from. In this first episode, Jeremiah Grossman (@jeremiahg), Robert Hansen (@RSnake) and I talk about interesting topics from the show floor.

In general, we had a blast in Denver trying out some craft beer during the OWASP pub crawl, hanging out with the awesome team from BugCrowd who hosted a Bug Smash, and mingling with some of the top AppSec people in the world. Next year’s AppSecUSA is in San Francisco so we can all go bug Michael Coates (@_mwc) in his backyard. Hope to see many of you there!

And now… HackerKast Episode 1:

What the InfoSec Skills Gap Means for the Future

One of the biggest challenges – if not the biggest challenge – facing information security is the lack of skilled talent. As yet another proof point in a long line of reports all saying the same thing, Cisco’s 2014 Annual Security Report says, “it’s estimated that by 2014, the [IT Security] industry will still be short more than a million security professionals across the globe.” You ask any hiring manager, and they’ll agree. And here’s the thing, we might be able to make a dent in the skill gap with education programs, but by-and-large, the information security skills shortage isn’t going to get solved any time soon.

This says to me…

  1. Breaches will continue at least at the current clip resulting in increased industry and government regulations, which will lead to compliance job openings.
  2. Compensation for competent information security personnel will continue to rise and globalize, regardless of whether the person is experienced or not.
  3. Organizations in the best position to hire, train, and retain security talent will carry the day. Education isn’t going to come in the form of reading or certification, but on the job in a more “trial by fire” way.
  4. Organizations will continue to outsource their security needs to where security talent can be best centralized and scaled.
  5. People with limited background in security will be increasingly tasked with performing security jobs – or at least managing the processes.
  6. Super easy-to-use security products and services will be preferred over the more technically sophisticated and feature rich.
  7. The information security skill shortage is actually going to get worse as the economy improves.

Everyone get busy automating!

So Your Nude Selfies Were Just Hacked…

If you haven’t been following the most recent news regarding a wide swath of celebrities whose accounts were hacked and private photos shared, you must have been having a lot of fun on Labor Day and I salute you.

Probably the very first thing most of the victimized celebrities are doing now is damage control – limiting their exposure as much as possible. Yes, their names are going to be put out there. Yes, it’s horribly embarrassing, but it’s also not a time to get caught up in self-pity (or self-blame): there’s work to be done. Being cool-headed and reducing the exposure will reduce the pain overall. Some people might go down the path of making examples out of the alleged perpetrators — but beware the Barbra Streisand effect. The harder you try to hide things, the more people want to see those things — like arial photos of Ms. Streisand’s lavish house, for instance.

But these events bring up an interesting point: What would you do if you were a celebrity who had dodged the bullet, but had similar incriminating photos on their computers, cell phones, etc.? More importantly, what should you be doing right now, this very minute, to make sure that anything you have posted to the cloud and want to keep private actually remains so?

First things first – locate every place that the sensitive information lives.
If it’s on a lover’s phone, an old computer that is collecting dust under your staircase, an old email account, or uploaded onto Dropbox – whatever the case may be, you need to find all of it and get an inventory of what those things are. Once you know what’s there, you have to find a way to securely delete that information. Just putting things in the trash can doesn’t work, unfortunately. Older computers have a knack for keeping lots of copies of things when discs defragment. So you need to securely wipe not only the data, but also the free-space on your computer.

Next use the “mud puddle” rule of thumb.
Ask the company that makes the system in question if there is any way to recover data after you have dumped it in a puddle of mud. If the answer is yes, you have a problem, because it means they have copies of your data and can decrypt it (if it was ever encrypted at all) and access it. Make sure that all copies are deleted and removed securely from all systems, and ask for some proof of that. In the worst case scenario, get your lawyer involved to make sure that all copies are securely and permanently deleted. You have two options with computers – either they are perfectly private and accessible only to you, or they have a high-level of convenience and availability. Choose one.

Next, remove all automated syncing to cloud-based systems.
There is no reason you should be sending all of your information to an environment that you don’t completely control. Find an IT guy to set up a private cloud instance that you can back up your computer to, and make sure you are the only one who can access that system once it’s set up if you have to store information off-site. There’s lots of precious family photos, and emails and documents that would be painful to lose. Back them up in a place that only you have access to.

Choose strong passwords.
It sounds simple but nearly every successful hack involving brute force relies on the individual accounts having weak passwords. Don’t fall for it: choose strong passwords, and make them unique. If your password for your free webmail is the same as for your critical systems that protect your nude pictures, you’re more likely to get hacked. It’s always the weakest link, so keep your passwords unique and strong. There’s a lot of password research out there that says that choosing a “passphrase” made up of several words in a row is the strongest sort of password. If you’re an actress, you are used to memorizing lines to get a part. Consider this just another script you need to memorize, but one that can protect your entire reputation. Or, even better, use “second factor authentication” – a physical token or something you have that cannot be stolen from the Internet, if your provider allows it.

Encrypt your nude selfies.
I’m not going to judge you — nude selfies aren’t bad, but they can be dangerous if you don’t encrypt them. There’s lots of encryption software out there and a great deal of it is free. You can choose something that encrypts your selfies when you’re not looking at them and decrypts them when you want to see them for some reason.

Send encrypted nude selfies.
Similar to the above, if you’re going to be sending nude selfies, make sure you do so in a way that self destructs. Software like Wickr can accomplish that for cell phones. There’s no reason to keep them around forever, and if you do need to keep them, you can always save them and re-send them later.

Don’t send nude selfies at all.
I know it sounds obvious and stupid, but once you become a celebrity, it’s really imperative to avoid sending anything incriminating or even keeping it around at all. If you do have to have it for some reason, make sure you keep it on a computer that isn’t capable of going online, so at least you can keep it compartmentalized. Systems that aren’t online are much harder to hack – and usually require physical access to your premises. This is the reason some militaries are reportedly going back to typewriters – it’s a lot harder to hack something physical without involving breaking and entering.

Pick strong secret questions.
One of the most often overlooked issues in computer security is the secret question. Most secret questions are terrible: “what is your favorite color?” Well, the chances that it’s one of a handful of colors is extremely high, and it’s even higher if you’re a celeb since no-doubt at some point someone asked you that on camera. This makes it extremely easy for someone to guess and therefore access your information. So lie and choose something else – some long string that only you know. Write it down somewhere so you don’t lose it, but keep it safe and unique – similar to passwords. Is your favorite color blue? I hope not. Is your birth date the same one that’s on IMDB? Please tell me no.

Disable everything you don’t need.
Living in LA does require you to use hands-free, and I’m sure driving down Venice Beach in your convertible sounds great, but at the same time every time you turn on wireless on your phone, or bluetooth or any additional service, you are putting yourself at greater risk. It’s all a matter of surface area, and the more things you can disable, the better.

Find a security pro.
I highly recommend you find a good security expert to analyze your life, and figure out how and where you are vulnerable. It might be something stupid and avoidable, like you leave your camera in a hotel room while you are away, or it might be something very complex having to do with configuration settings on your home Wifi. Whatever the case, you really should have someone who knows what they are doing take a look at how you live and give you practical advice on how to protect yourself.

It’s easy to blame the victims, and that’s the very last thing I’d ever want to do. I think, if anything, this just shows what a large percentage of people take nude pictures of themselves, so we can’t judge. But there are definitely a few steps people can take to avoid some of the embarrassment. For those who dodged the bullet, consider yourselves lucky; but perhaps it’s time to take your lucky winning streak and leave the blackjack table while there is still time.

6 Reasons Why ‘Security Guarantees’ Are Good For The Security Community

Since Sentinel Elite was announced, we’ve experienced an exciting amount of interest in it’s money-back guarantee and $250,000 financial coverage for damages suffered if a customer is breached via a vulnerability that we should have discovered but missed. Over the last few weeks, the security community has been buzzing with chatter about software liability, cyber-insurance, and security guarantees. There is an opportunity here for the information security industry to up its game. When done right, security guarantees are going to be really good for the security community. Here’s why:

  1. Truly effective security products become easier for customers to differentiate from those that are…less effective. Similar to how we look at the purchase of cars, electronics, and more, some products have better warranties than others, which signals less purchase risk for the buyer and an increase in perceived quality.
  2. The credibility of the security industry, or individual vendor, is improved because we hold ourselves accountable for the performance of our products. Let’s face it. Security vendors don’t always have a great reputation when viewed by those outside the industry. One argument for why this is, is that when our advice or products fail, we’re not on the hook. Many vendors even profit when disaster strikes, yet the victims – our customers – are left cleaning up the mess. By making ourselves accountable in the event of a breach we can turn this perception around and prove that our goals do align with our customers.
  3. We receive performance and actuarial data that can be directly used to increase the effectiveness of our products. The upside on having to pay-out on a failure to live up to a security guarantee is that we get hard data on what really went wrong. This data is helpful because it tells us why the security control didn’t stop the bad guy. This data is pure gold for product development.
  4. It gives us the ability to quantify and convey the value of security products in dollars and cents. Most often business owners really don’t get the value of what it is that a security product does. We speak in esoteric terms about ‘vulnerability,’ ‘risk,’ ‘threat,’ ‘zero-day,’ and so on – very rarely do we speak in business terms or in dollars and cents that the business owner can truly understand. With security guarantees we can give stakeholders – those who pay for our solutions – a way to understand the value we bring to the business in language they understand and can plug into their financial spreadsheets.
  5. The business interests of a security company are in line with the customer and decisions are made accordingly. One of the most frustrating things for a security professional is encountering situations when what a customer really needs to be more secure is not necessarily what is beneficial for the security vendor. Customers want to spend money on products that help them protect against getting hacked. When vendors provide security guarantees, the highest priority is doing exactly that, which creates a true partnership between the vendor and the customer.
  6. Security guarantees enable defense-in-depth strategies to transcend the concept of simply buying multiple security products to protect the business in the event of financial loss. We know security products are not perfect or all-encompassing, so multiple solutions are needed to guard against breach under this eventuality. With a security guarantee, when all is said and done, the customer is still protected in the event that everything fails – which is more common than not these days.

We continue to appreciate the feedback on this topic and are very much interested in what our customers and the rest of the industry has to say about this. What other reasons are there – positive or negative – for having security guarantees? We would welcome your suggestions in the comments below.

Aviator (Default) Search Change

In an effort to find ways to work with a search provider, we spent a lot of time researching various models that would enable us to stay on the side of our users AND allow us to generate revenue to help us pay for Aviator development. Naturally we attempted to work with DuckDuckGo since they were already our search provider of choice. Unfortunately, the only way they were willing to work with us was to monetize ads, and we just aren’t willing to do that. Browsers monetizing ads is at the root of what’s causing issues for users, stifling security and eliminating privacy.

After months of work we decided that Disconnect Search was the best and most exciting path forward. We have a long-standing relationship with the Disconnect team because of their popular browser plugin, and their privacy record is spotless — and Disconnect was comfortable working a deal with us that didn’t rely on selling ads. You can’t beat that! We were thrilled to find a partner who cares enough about their users and ours to forgo the typical death cycle of mandatory partnerships that revolve around advertising, and instead just revolve around being the default search.

This is just another way we want to be clear that we are on our customer’s side, even in matters of business. Our transparency with our business model is the crux of why our users can trust our decisions to be in their best interest. So, in the coming update you will notice that the browser politely asks you if you want to switch from DuckDuckGo to Disconnect. The option is yours, of course, but this will help us continue to evolve the browser, and we believe Disconnect is the most private search engine we could find to boot. Two birds with one stone, right?!

As always, questions and comments are welcome!