INSIGHTS, NEWS & DISCOVERIES
FROM IOACTIVE RESEARCHERS

Tuesday, November 18, 2014

Die Laughing from a Billion Laughs

By Fernando Arnaboldi

Recursion is the process of repeating items in a self-similar way, and that’s what the XML Entity Expansion (XEE)[1] is about: a small string is referenced a huge number of times. 

Technology standards sometimes include features that affect the security of applications. Amit Klein found in 2002 that XML entities could be used to make parsers consume an unlimited amount of resources and then crash, which is called a billion laughs attack. When the XML parser tries to resolve, the external entities that are included cause the application to start consuming all the available memory until the process crashes. 

Thursday, November 6, 2014

ELF Parsing Bugs by Example with Melkor Fuzzer

By Alejandro Hernandez @nitr0usmx

(Extract from white paper at http://www.ioactive.com/pdfs/IOActive_ELF_Parsing_with_Melkor.pdf )


Too often the development community continues to blindly trust the metadata in Executable and Linking Format (ELF) files. In this paper, Alejandro HernĂ¡ndez walks you through the testing process for seven applications and reveals the bugs that he found. He performed the tests using Melkor, a file format fuzzer he wrote specifically for ELF files.