During security assessments, I always make sure they’re performing security testing as part of their development process. This is why: “Apple security blunder exposes Lion login passwords in clear text” No need to go into details as to what happened here; it’s well-researched in the linked article. However, this is exactly the scenario that development security testing is meant to avoid. A seemingly innocent patch disables or circumvents an important security feature. The results are predictable. It could be worse, though. Here’s the worst case: the problem isn’t detected. Because the security was included in the original version, and because nobody checked, it is assumed that the security is in place, and successive updates are made, with the security feature[…]

tl;dr Abstract To improve performance, particularly for mobile users, many websites have started caching app logic on client devices via HTML5 local storage. Unfortunately, this can make common injection vulnerabilities even more dangerous, as malicious code can invisibly persist in the cache. Real-world examples of this problem have now been discovered in third-party “widgets” embedded across many websites, creating security risks for the companies using such services – even if their sites are otherwise protected against attacks. Striking a balance between security and performance can be difficult, but certain precautions may help prevent an attacker from exploiting local storage caches. Background Throughout the history of web development, people have found ways to use and abuse various technologies beyond their intended[…]

One of the biggest complaints I’ve had with VMWare vSphere and VMWare ESX/ESXi over the last few years is that managing my virtual machines from my Mac computer was a hassle. The VMWare management utilities are all Windows-only, and even the few web-based tools either do not work or are extremely limited from a Mac. While it isn’t perfect yet, VMWare vSphere 5 has made it so you can actually do just about anything you need to using a Macintosh computer; you just need to go through a few hurdles. To enable the administration of your various virtual machines, storage, clusters, datacenters, and the like, you can now use the vSphere 5 Web Client. Before it can be used, it must[…]

Security researcher Mario Heiderich (also creator of the HTML5 Security Cheatsheet and lead developer for PHPIDS) has been posting some interesting cross-site scripting challenges lately that highlight aspects of security on the client side. The most recent, called XSSMe², involved a page with a reflected XSS vulnerability that allowed one to insert arbitrary HTML – no filters applied by the server. The goal? Retrieve a particular bit of data, originally stored in document.cookie, without any user interaction. I say “originally,” because the page included JavaScript which attempted to lock down access to the data by removing it from document.cookie and hiding it unless retrieved by a user click. The code used evolved as bypasses were found, with several tricks employed along[…]

I often talk about cross-site scripting (XSS), and that’s partly because I think it’s a pretty interesting type of vulnerability that many developers tend to overlook. It can be quite dangerous, but can also be quite misunderstood. For one thing, the name can be misleading: exploiting XSS does not always involve scripting, and the proliferation of web technologies has taken XSS issues beyond the browser. One example of script-less cross-site scripting affected some high-profile MySpace users in 2007. Attackers were able to inject HTML into celebrity MySpace pages, but the service filtered out typical <script> payloads. Seemingly innocent <a> links were allowed, though, and adding a bit of CSS allowed one to create an invisible link that covered the entire[…]

If you’re new to the world of testing web application security, you may not be aware of the many great Firefox add-ons available that greatly help such endeavors. While others have compiled similar lists in the past, I thought this week would be a good time for me to share a few of the favorite tools I use in my own web app work. HttpFox: I’ve blogged about this one in the past; it lists for you every HTTP request made during a given browser session, with details on headers, cookies, parameters, responses, and more. Very handy to monitor traffic when you’re browsing around an app. HackBar: Another one I’ve mentioned before, the HackBar is a swiss-army knife that gives[…]