Mobile code: invoking untrusted mobile code

Description
This attack consists of a manipulation of a mobile code in order to execute malicious operations at the client side. By intercepting client traffic using the man-in-the-middle technique, a malicious user could modify the original mobile code with arbitrary operations that will be executed on the client’s machine under his credentials. In another scenario, the malicious mobile code could be hosted in an untrustworthy web site or it could be permanently injected on a vulnerable web site through an injection attack. This attack can be performed over Java or C++ applications and affects any operating system.

Risk Factors
TBD

Examples
The following code demonstrates how this attack could be performed using a Java applet.

// here declarer a object URL with the path of the malicious class URL[] urlPath= new URL[]{new URL("file:subdir/")};

// here generate a object “loader” which is responsible to load a class in the URL path URLClassLoader classLoader = new URLClassLoader(urlPath);

//here declare a object of a malicious class contained in “classLoader” Class loadedClass = Class.forName("loadMe", true, classLoader);

To solve this issue, it’s necessary to use some type of integrity mechanism to assure that the mobile code has not been modified.

Related Threat Agents

 * TBD

Related Attacks

 * Mobile code: non-final public field
 * Mobile code: object hijack

Related Vulnerabilities

 * Category: Unsafe Mobile Code

Related Controls

 * Hashing
 * Bounds Checking
 * Safe Libraries
 * Static Code Analysis
 * Executable space protection
 * Address space layout randomization (ASLR)
 * Stack-smashing Protection (SSP)