How to Hack Web Applications

I’ve been evaluating Google’s Web Application and Defences tutorial over the past day or so. Based around a fictitious Web application called Jarlsberg, it consists of a series of exercises that allow the student to exploit the numerous security holes on the site. The vulnerabilities include Cross Site Scripting (XSS) in its many forms, Cross Site Request Forgery (XSRF), Path Traversal, Denial of Service (DoS), Privilege Escalation, AJAX vulnerabilities and remote code execution. The main absentees are SQL injection and buffer over flows.

Although a basic understanding of HTML and Javascript is necessary to understand the content, you don’t need to be an experienced web developer to benefit from the tutorial. Its main plus point is seeing exploits in action to demonstrate the damage they can cause. In the past I’ve sometimes had problems explaining quite why something like an XSRF vulnerability is a risk to a web site.

Microsoft Security Intelligence Report Vol 8 Published

Microsoft has published its security intelligence report for the second half of 2009. The information is gathered by Microsoft security tools including the Malicious Software Removal tool, run before Windows Updates are installed, and Microsoft Security Essentials.

One of the main claims is that if you run Windows 7 or Vista rather than XP, you are more likely to be exposed to vulnerabilities in third party software most notably from Adobe, than to vulnerabilities in Microsoft products. Worldwide it seems that a PC is most likely to be infected by a Worm from the Tartef family which targets online game players, although malware patterns vary from country to country.

Fake security software is also prevalent as are botnets used for sending SPAM.

Top 10 Web Application Security Risks

The Open Web Application Security Project, OWASP, has published the 2010 version of its top 10 web application security risks, the first revamp since 2007. Recognised as a key information tool for developers and security professionals, the OWASP top 10 is referenced in many security standards including PCI DSS.

Although there are many similarities with the 2007 edition, the emphasis has been changed to reflect security risks rather than just vulnerabilities. Prominent as ever are cross site scripting, XSS, and injection vulnerabilities which have caught out both Apache and Amazon in recent weeks.

Added to the Top 10 is Security Misconfiguration. Left out of the 2007 edition as it wasn't considered to be a software issue, it was re-added to reflect the emphasis on risk. Also new is Unvalidated Redirects and Forwards. Relatively unknown as an issue, OWASP suggests that that its potential for damage is high.

Removed from the Top 10 is Malicious File Execution. Although still an issue, improvements in the default configuration of PHP where the problem was most widespread, has led to a reduction in incidents. Information Leakage and Improper Error Handling is also removed. Again, while still prevalent direct risk is minimal.

Security and Legal Issues in the Cloud

I recently tuned in to a Webinar on Security and Legal issues in the Cloud. I was pleased to find that most of the presenters started from the view point that Cloud technology is mainly rebranding of existing services and so many of the issues are what we know and are used to.

One of the main differences is not surprisingly trust levels. The more you outsource your services to the Cloud the more you need to have confidence in a third party to correctly handle your data and intellectual property. This can be achieved to a degree by the certifications and reputation of the supplier but it’s important to carry out your own audits.

Authentication was also heavily discussed during the presentations. One of the common side effects of Cloud Systems is the necessity to introduce yet another authentication level for the user population which of course is never popular. One of the presenters proposed federated authentication as a solution, particularly SAML and OpenID. These technologies as well as others have been around for a while but never seem to have got the momentum they might have.

Data protection is another area that needs some thought. It’s important to know where your data is held as it is governed by the laws of the country where it is located as well as those from which it is accessed. Regulation is very different from country to country and particularly between North America and Europe.

Although not directly related to the Webinar’s main subject, the undercurrent of the presentations was perhaps the most important. Cloud Computing is currently in fashion which has lead to many “Cloud” solutions being implemented when perhaps they shouldn’t have been. You would hope that the technology industry would be based more on fact that fashion but unfortunately that doesn’t seem to be the case.

UK Digital Economy Act Encourages Innovation

The part of the UK Digital Economy Act designed to discourage illegal downloading has inadvertently initiated furious discussion about how best to anonymize Bit Torrent and other file sharing traffic. Only this morning an article on the Register speculated that the SeedF*cker code, originally considered an exploit, could be used to disguise the IP address of a server hosting illegal content. Although many commentators were quick to dispute this, it does appear that there are plenty of ideas out there on how to beat the snoopers.

Not surprisingly, many proposed solutions are based around encryption and VPNs but there are also more novel suggestions such as routing all traffic via countries with strong data protection laws or dividing files into extremely small chunks making them hard to identify. Some companies already claim to offer solutions.

There is also the so called darknet which offers solutions for remaining anonymous.

How Much is Your Online Privacy Worth?

How much is your online privacy worth? In the UK it appears that until recently it was no more than £5000, which was the maximum the Data Protection Commissioner could fine companies who committed a serious breach. The Register reports that figure has just been raised to £500 000 which should hopefully focus data custodians into taking data protection a little more seriously.

Google. What They Know About You Explained.

With yet another Google Privacy story in the news today, I thought it would be interesting to examine exactly what Google knows about the average internet user and how they gather their information. To simplify the article I have excluded any Google services that require some kind of authentication such as Gmail or Google Apps. All the information discussed below is harvested from so called anonymous browsing.

Firstly, irrespective of your Internet browser or even the HTTP protocol, every time you visit a web site, you must send your IP address to the destination so that the receiver knows where to send the reply. If you are a home user your IP address is allocated on a semi random basis from a large pool managed by your ISP. Even so, publicly available online tools can be used to narrow down your location from your IP address to at least the nearest city to where you browse from. Many sites use this information to target advertising at you. This is most obvious if you browse a site in a different country but see advertisements in your local language specific to businesses or services from your country. Your ISP of course can use the IP address to uniquely identify you.

Again, even before you start using Google products or web sites, each time you access a new web page you send the web server certain information contained in “headers”. One of these is called the user agent which tells the website your browser type and operating system.

So, before you even type the first character into Google’s search engine, they already know more or less where you live, your operating system and your browser type. This of course is not limited to Google but applies to any web site. Once you do access www.google.com for the first time you receive a cookie, nominally to record your preferences, e.g. language, number of results per page etc, but which also contains a unique ID. The next time you access the Google site the cookie, which is stored on your hard drive, is read and the ID from the first visit retrieved. Each search you perform is recorded by Google together with the ID to build up profile of your browsing habits. The information is used to target advertising at you, with the targeting becoming more effective as your profile expands.

Things get even more interesting for users of Google’s Chrome internet browser. As Microsoft highlighted last week, the address bar of Chrome is also the search bar. Every key stroke typed into the address/search bar is sent to Google to allow for an auto suggest of the term you may want to search for or the site you wish to browse to. Guess what. Your Google cookie containing the unique ID is also sent to Google allowing them to record every site you visit.

Many commentators also flag Google Analytics as a way Google can record your internet activity even if your web usage habits prohibit use of the previously mentioned techniques. Google Analytics allow web masters to record usage statistics for their site. It works by including a small amount of java script on each page that sends information to Google about the user’s activity. From what I can see, it doesn’t send the Google cookie and so identifying a user is limited to IP address.

What does this mean in practise? In a worst case scenario, a law enforcement agency with complicity from Google and your ISP can build a complete record of your internet browsing including time and location information. Eric Schmidt, Google’s CEO, has previously stated that if you’ve nothing to hide then what’s the problem? This may be true if you live in a Western Democracy although many people would argue otherwise. It’s certainly not the case if you live in a country where the human rights’ record is less ideal.

In European countries at least, abuse of this data is prohibited by the European Data Protection Directive and the country based laws that reflect it. This is just as well as imagine your employer, or anyone else for that matter, being able to get hold of all your internet activity including that from your home PC.

It’s also worth pointing out that none of these data gathering techniques are unique to Google but as it is the biggest player in the internet space, they can gather the most data and consequently attract the most criticism when people complain about privacy issues.

In theory there are a few things you can do to limit the information that you leak to Google. The simplest is to delete you cookies on a regular basis which makes it much harder to track your activity. There are also services like GoogleSharing that anonymise your Google traffic, but in reality you can never completely hide your browsing patterns. If you want to use the internet to the full, it is necessary to accept that some of your privacy is lost.