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With the rapid expansion of the Internet of Things, a vast number of microcontroller-based IoT devices are now susceptible to attacks through the Internet. Vulnerabilities within the firmware are one of the most important attack surfaces. Fuzzing has emerged as one of the most effective techniques for identifying such vulnerabilities. However, when applied to IoT firmware, several challenges arise, including: (1) the inability of firmware to execute properly in the absence of peripherals, (2) the lack of support for exploring input spaces of multiple peripherals, (3) difficulties in instrumenting and gathering feedback, and (4) the absence of a fault detection mechanism. To address these challenges, we have developed and implemented an innovative peripheral-independent hybrid fuzzing tool called . This tool enables testing of microcontroller-based firmware without reliance on specific peripheral hardware. First, a unified virtual peripheral was integrated to model the behaviors of various peripherals, thus enabling the physical devices-agnostic firmware execution. Then, a hybrid event generation approach was used to generate inputs for different peripheral accesses. Furthermore, two-level coverage feedback was collected to optimize the testcase generation. Finally, a plugin-based fault detection mechanism was implemented to identify typical memory corruption vulnerabilities. A Large-scale experimental evaluation has been performed to show ’s effectiveness and efficiency.
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Exploiting Memory Corruption Vulnerabilities in Connman for IoT Devices
In the recent past, there has been a rapid increase in attacks on consumer Internet-of-Things (IoT) devices. Several attacks currently focus on easy targets for exploitation, such as weak configurations (weak default passwords). However, with governments, industries, and organizations proposing new laws and regulations to reduce and prevent such easy targets in the IoT space, attackers will move to more subtle exploits in these devices. Memory corruption vulnerabilities are a significant class of vulnerabilities in software security through which attackers can gain control of the entire system. Numerous memory corruption vulnerabilities have been found in IoT firmware already deployed in the consumer market. This paper presents an approach for exploiting stack-based buffer-overflow attacks in IoT firmware, to hijack the device remotely. To show the feasibility of this approach, we demonstrate exploiting a common network software application, Connman, used widely in IoT firmware such as Samsung smart TVs. A series of experiments are reported on, including: crashing and executing arbitrary code in the targeted software application in a controlled environment, adopting the attacks in uncontrolled environments (with standard software defenses such as W⊕X and ASLR enabled), and installing publicly available IoT firmware that uses this software application on a Raspberry Pi. The presented exploits demonstrate the ease in which an adversary can control IoT devices.
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- Award ID(s):
- 1757884
- PAR ID:
- 10135009
- Date Published:
- Journal Name:
- 49th Annual IEEE/IFIP International Conference on Dependable Systems and Networks (DSN)
- Page Range / eLocation ID:
- 247 to 255
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/DSN.2019.00036
