PDF files have become commonplace on the Internet and in the business world, but they have also become favorite tools for attackers to deliver malicious payloads. While some problems may be mitigated by using an alternative PDF reader, many people have little choice but to use the standard Adobe Reader. In that situation, you can help protect yourself from many PDF-based attacks by following a few basic steps. Make sure you have an up-to-date anti-malware program installed and running with automatic download of new virus definitions. Older tools may not scan for recent PDF-based threats. Make sure you have the latest version of Adobe Reader. Enable automatic updates by opening Reader and choosing Edit > Preferences > Updater. Adobe regularly[…]
Category: software
Browser security is a topic that spans a wide range of subjects. This isn’t surprising given the number of exploit techniques that rely on webpages as a primary delivery channel in their attacks. Successful XSS, CSRF, SQL injection (via web app), and plug-in-based attacks all take advantage of the environment provided by the web browser. Despite the importance of the browser in the chain of security, information on exactly how it goes about managing javascript across domains and determining when to show the “save as” download dialog can be overlooked. However, this is an area where attackers may concentrate their efforts to hedge out new exploits based on a weakness in browser security. The Browser Security Handbook, released in 2008,[…]
In evaluating web application security, I’ve built up a toolbox of Firefox add-ons that make testing and experimenting much easier than manual techniques. One of my favorites is a little tool called HttpFox. While no match for a professional HTTP sniffer, HttpFox provides enough functionality for many basic testing situations. If you want to see what’s happening behind the scenes for a given web application, HttpFox lets you pull up a traffic log without leaving your browser. The plug-in displays a panel right in the lower half of the window and captures a list of every HTTP request made during a given session. (You control the capture through start and stop buttons.) Highlighting an individual request brings up detailed information[…]
Last week, Google labs released a new free web analyzer tool called Skipfish (project details here). I haven’t had a chance to play with it yet, although I hope to soon, since I have a new web application almost ready to go live. Skipfish appears to support a ton of features, such as “Multiplexing single-thread, fully asynchronous network I/O and data processing model that eliminates memory management, scheduling, and IPC inefficiencies present in some multi-threaded clients.” Which, although I only barely can understand it, sounds very impressive. The vulnerabilities scanned for include: High risk flaws (potentially leading to system compromise): Server-side SQL injection (including blind vectors, numerical parameters). Explicit SQL-like syntax in GET or POST parameters. Server-side shell command injection[…]
Earlier this week, news reports surfaced of a security hole in a popular mobile application for sharing photos. The program, called Quip, enabled iPhone users to send picture messages to any phone without using carriers’ MMS technology, which often requires an extra monthly fee. Quip sent text messages or push notifications with a link to a web page where the recipient could view the intended picture. According to the developers of Quip, users have sent over 3 million photos using the service. But those 3 million photos did not only reach their intended viewers. The application uploaded pictures to a public web server with no encryption or authentication, and even worse, the addresses of the files followed a simple, predictable[…]
In general, Windows does a decent enough job with securing software keys in CAPI. Sure, you can open up Windows Explorer, browse to C:\ProgramData\Microsoft\Crypto\RSA\MachineKeys, and take a look at your private key files. These bare files, of course, are not exactly plain text. The RSA Machine Keys (which include private keys corresponding to software certificates), are encrypted using the Data Protection API (DPAPI). The DPAPI encryption method is based on the use of a Master Key – a 512 bit random blob that is created using PKCS #5 Password-Based Key Derivation. This process takes the user’s account password, applies the SHA-1 hash algorithm, sends the hash plus a salt to the key derivation algorithm, and then iteratively calls another PKCS[…]