Static Exploration of Taint-Style Vulnerabilities Found by Fuzzing

Authors: 

Bhargava Shastry, Technische Universität Berlin; Federico Maggi, Trend Micro Inc.; Fabian Yamaguchi and Konrad Rieck, Technische Universität Braunschweig; Jean-Pierre Seifert, Technische Universität Berlin

Abstract: 

Taint-style vulnerabilities comprise a majority of fuzzer discovered program faults. These vulnerabilities usually manifest as memory access violations caused by tainted program input. Although fuzzers have helped uncover a majority of taint-style vulnerabilities in software to date, they are limited by (i) extent of test coverage; and (ii) the availability of fuzzable test cases. Therefore, fuzzing alone cannot provide a high assurance that all taint-style vulnerabilities have been uncovered.

In this paper, we use static template matching to find recurrences of fuzzer-discovered vulnerabilities. To compensate for the inherent incompleteness of template matching, we implement a simple yet effective match-ranking algorithm that uses test coverage data to focus attention on matches comprising untested code. We prototype our approach using the Clang/LLVM compiler toolchain and use it in conjunction with afl-fuzz, a modern coverage-guided fuzzer. Using a case study carried out on the Open vSwitch codebase, we show that our prototype uncovers corner cases in modules that lack a fuzzable test harness. Our work demonstrates that static analysis can effectively complement fuzz testing, and is a useful addition to the security assessment tool-set. Furthermore, our techniques hold promise for increasing the effectiveness of program analysis and testing, and serve as a building block for a hybrid vulnerability discovery framework.

Open Access Media

USENIX is committed to Open Access to the research presented at our events. Papers and proceedings are freely available to everyone once the event begins. Any video, audio, and/or slides that are posted after the event are also free and open to everyone. Support USENIX and our commitment to Open Access.

BibTeX
@inproceedings {206158,
title = {Static Exploration of Taint-Style Vulnerabilities Found by Fuzzing},
booktitle = {11th {USENIX} Workshop on Offensive Technologies ({WOOT} 17)},
year = {2017},
address = {Vancouver, BC},
url = {https://www.usenix.org/conference/woot17/workshop-program/presentation/shastry},
publisher = {{USENIX} Association},
}