SourceSec Security Research Group

I’ve just published a new article on my column over at Ethical Hacker describing the UPNP protocol, and how to hack it using Miranda. Don came up with a great image for the article too…you can check it out here!

We’ve been taking a close look at some popular SOHO routers lately, and have started to find some really interesting stuff. It’s actually a little disconcerting - I don’t think that we have seen a router that doesn’t contain some type of exploitable vulnerability. We’ve written up a preliminary paper detailing some of the issues that we’ve discovered; there are some other, more serious issues that we’re still in the middle of investigating and we’ll hopefully have more information about those up here soon. An excerpt from the introduction:

With embedded devices permeating today’s home networks, they have begun to attract a higher level of scrutiny from the security community than in previous years. In particular, the members of GNUCitizen have been relentlessly testing routers and wireless access points. Their discovery of multiple vulnerabilities in the BT Home Hub router affected a wide range of home networks in the UK [1], and their Router Hacking Challenge prompted a flurry of vulnerability reports against a variety of popular home routers, including the venerable Linksys WRT54G [2]. Specific vulnerabilities in home routers range from traditional Web attacks, such as XSS and CSRF, to authentication bypass attacks and buffer overflows; it is assumed that the reader has at least a passing knowledge of the attacks described in this paper.

The purpose of this paper is to outline the security measures being taken by vendors to prevent such attacks in their home routing products, what those security measures accomplish, and where they fall short. We will use existing network tools to examine common vulnerabilities in a range of popular devices and demonstrate weaknesses in the security of those devices; additionally, we will examine common trends in security measures that have been duplicated across vendors, and examine how those trends help and hinder the security of their devices. In particular, we will examine the following home routers, which are some of the latest offerings from their respective vendors at the time of this writing:

 

• Linksys WRT160N
• D-Link DIR-615
• Belkin F5D8233-4v3
• ActionTec MI424-WR

Read the entire article here.

In Windows, all applications must communicate with the kernel through API functions; as such, these functions are critical to even the simplest Windows application. Thus, the ability to intercept, monitor, and modify a program’s API calls, commonly called API hooking, effectively gives one full control over that process. This can be useful for a multitude of reasons, including debugging, reverse engineering, and hacking (in all interpretations of the word).

While there are several methods which can be used to achieve our goal, this tutorial will examine only DLL redirection. This approach was chosen for several reasons:

• It is relatively simple to implement.
• It allows us to view and modify parameters passed to an API function, change return values of that function, and run any other code we desire.
• While most other methods require code to be injected into the target process or run from an external application, DLL redirection requires only write access to the target application’s working directory.
• We can intercept any API call without modifying the target (either on disk or in memory) or any system files.

The full article has been posted on EthicalHacker.net and milw0rm.com.