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- All Subjects: Computer Science
- Creators: Doupe, Adam
Description
Advancements in computer vision and machine learning have added a new dimension to remote sensing applications with the aid of imagery analysis techniques. Applications such as autonomous navigation and terrain classification which make use of image classification techniques are challenging problems and research is still being carried out to find better solutions. In this thesis, a novel method is proposed which uses image registration techniques to provide better image classification. This method reduces the error rate of classification by performing image registration of the images with the previously obtained images before performing classification. The motivation behind this is the fact that images that are obtained in the same region which need to be classified will not differ significantly in characteristics. Hence, registration will provide an image that matches closer to the previously obtained image, thus providing better classification. To illustrate that the proposed method works, naïve Bayes and iterative closest point (ICP) algorithms are used for the image classification and registration stages respectively. This implementation was tested extensively in simulation using synthetic images and using a real life data set called the Defense Advanced Research Project Agency (DARPA) Learning Applied to Ground Robots (LAGR) dataset. The results show that the ICP algorithm does help in better classification with Naïve Bayes by reducing the error rate by an average of about 10% in the synthetic data and by about 7% on the actual datasets used.
ContributorsMuralidhar, Ashwini (Author) / Saripalli, Srikanth (Thesis advisor) / Papandreou-Suppappola, Antonia (Committee member) / Turaga, Pavan (Committee member) / Arizona State University (Publisher)
Created2011
Description
One of the main challenges in planetary robotics is to traverse the shortest path through a set of waypoints. The shortest distance between any two waypoints is a direct linear traversal. Often times, there are physical restrictions that prevent a rover form traversing straight to a waypoint. Thus, knowledge of the terrain is needed prior to traversal. The Digital Terrain Model (DTM) provides information about the terrain along with waypoints for the rover to traverse. However, traversing a set of waypoints linearly is burdensome, as the rovers would constantly need to modify their orientation as they successively approach waypoints. Although there are various solutions to this problem, this research paper proposes the smooth traversability of the rover using splines as a quick and easy implementation to traverse a set of waypoints. In addition, a rover was used to compare the smoothness of the linear traversal along with the spline interpolations. The data collected illustrated that spline traversals had a less rate of change in the velocity over time, indicating that the rover performed smoother than with linear paths.
ContributorsKamasamudram, Anurag (Author) / Saripalli, Srikanth (Thesis advisor) / Fainekos, Georgios (Thesis advisor) / Turaga, Pavan (Committee member) / Arizona State University (Publisher)
Created2013
Description
The exponential rise in unmanned aerial vehicles has necessitated the need for accurate pose estimation under any extreme conditions. Visual Odometry (VO) is the estimation of position and orientation of a vehicle based on analysis of a sequence of images captured from a camera mounted on it. VO offers a cheap and relatively accurate alternative to conventional odometry techniques like wheel odometry, inertial measurement systems and global positioning system (GPS). This thesis implements and analyzes the performance of a two camera based VO called Stereo based visual odometry (SVO) in presence of various deterrent factors like shadows, extremely bright outdoors, wet conditions etc... To allow the implementation of VO on any generic vehicle, a discussion on porting of the VO algorithm to android handsets is presented too. The SVO is implemented in three steps. In the first step, a dense disparity map for a scene is computed. To achieve this we utilize sum of absolute differences technique for stereo matching on rectified and pre-filtered stereo frames. Epipolar geometry is used to simplify the matching problem. The second step involves feature detection and temporal matching. Feature detection is carried out by Harris corner detector. These features are matched between two consecutive frames using the Lucas-Kanade feature tracker. The 3D co-ordinates of these matched set of features are computed from the disparity map obtained from the first step and are mapped into each other by a translation and a rotation. The rotation and translation is computed using least squares minimization with the aid of Singular Value Decomposition. Random Sample Consensus (RANSAC) is used for outlier detection. This comprises the third step. The accuracy of the algorithm is quantified based on the final position error, which is the difference between the final position computed by the SVO algorithm and the final ground truth position as obtained from the GPS. The SVO showed an error of around 1% under normal conditions for a path length of 60 m and around 3% in bright conditions for a path length of 130 m. The algorithm suffered in presence of shadows and vibrations, with errors of around 15% and path lengths of 20 m and 100 m respectively.
ContributorsDhar, Anchit (Author) / Saripalli, Srikanth (Thesis advisor) / Li, Baoxin (Committee member) / Papandreou-Suppappola, Antonia (Committee member) / Arizona State University (Publisher)
Created2010
Description
Honeypots – cyber deception technique used to lure attackers into a trap. They contain fake confidential information to make an attacker believe that their attack has been successful. One of the prerequisites for a honeypot to be effective is that it needs to be undetectable. Deploying sniffing and event logging tools alongside the honeypot also helps understand the mindset of the attacker after successful attacks. Is there any data that backs up the claim that honeypots are effective in real life scenarios? The answer is no.Game-theoretic models have been helpful to approximate attacker and defender actions in cyber security. However, in the past these models have relied on expert- created data. The goal of this research project is to determine the effectiveness of honeypots using real-world data. So, how to deploy effective honeypots? This is where honey-patches come into play. Honey-patches are software patches designed to hinder the attacker’s ability to determine whether an attack has been successful or not. When an attacker launches a successful attack on a software, the honey-patch transparently redirects the attacker into a honeypot. The honeypot contains fake information which makes the attacker believe they were successful while in reality they were not.
After conducting a series of experiments and analyzing the results, there is a clear indication that honey-patches are not the perfect application security solution having both pros and cons.
ContributorsChauhan, Purv Rakeshkumar (Author) / Doupe, Adam (Thesis advisor) / Bao, Youzhi (Committee member) / Wang, Ruoyu (Committee member) / Arizona State University (Publisher)
Created2022
Description
Human civilization within the last two decades has largely transformed into an online one, with many of its associated activities taking place on computers and complex networked systems -- their analog and real-world equivalents having been rendered obsolete.These activities run the gamut from the ordinary and mundane, like ordering food, to complex and large-scale, such as those involving critical infrastructure or global trade and communications.
Unfortunately, the activities of human civilization also involve criminal, adversarial, and malicious ones with the result that they also now have their digital equivalents.
Ransomware, malware, and targeted cyberattacks are a fact of life today and are instigated not only by organized criminal gangs, but adversarial nation-states and organizations as well.
Needless to say, such actions result in disastrous and harmful real-world consequences. As the complexity and variety of software has evolved, so too has the ingenuity of attacks that exploit them; for example modern cyberattacks typically involve sequential exploitation of multiple software vulnerabilities.Compared to a decade ago, modern software stacks on personal computers, laptops, servers, mobile phones, and even Internet of Things (IoT) devices involve a dizzying array of interdependent programs and software libraries, with each of these components presenting attractive attack-surfaces for adversarial actors.
However, the responses to this still rely on paradigms that can neither react quickly enough nor scale to increasingly dynamic, ever-changing, and complex software environments.
Better approaches are therefore needed, that can assess system readiness and vulnerabilities, identify potential attack vectors and strategies (including ways to counter them), and proactively detect vulnerabilities in complex software before they can be exploited. In this dissertation, I first present a mathematical model and associated algorithms to identify attacker strategies for sequential cyberattacks based on attacker state, attributes and publicly-available vulnerability information.Second, I extend the model and design algorithms to help identify defensive courses of action against attacker strategies.
Finally, I present my work to enhance the ability of coverage-based fuzzers to identify software vulnerabilities by providing visibility into complex, internal program-states.
ContributorsPaliath, Vivin Suresh (Author) / Doupe, Adam (Thesis advisor) / Shoshitaishvili, Yan (Thesis advisor) / Wang, Ruoyu (Committee member) / Shakarian, Paulo (Committee member) / Arizona State University (Publisher)
Created2023
Description
The rise in popularity of applications and services that charge for access to proprietary trained models has led to increased interest in the robustness of these models and the security of the environments in which inference is conducted. State-of-the-art attacks extract models and generate adversarial examples by inferring relationships between a model’s input and output. Popular variants of these attacks have been shown to be deterred by countermeasures that poison predicted class distributions and mask class boundary gradients. Neural networks are also vulnerable to timing side-channel attacks. This work builds on top of Subneural, an attack framework that uses floating point timing side channels to extract neural structures. Novel applications of addition timing side channels are introduced, allowing the signs and arrangements of leaked parameters to be discerned more efficiently. Addition timing is also used to leak network biases, making the framework applicable to a wider range of targets. The enhanced framework is shown to be effective against models protected by prediction poisoning and gradient masking adversarial countermeasures and to be competitive with adaptive black box adversarial attacks against stateful defenses. Mitigations necessary to protect against floating-point timing side-channel attacks are also presented.
ContributorsVipat, Gaurav (Author) / Shoshitaishvili, Yan (Thesis advisor) / Doupe, Adam (Committee member) / Srivastava, Siddharth (Committee member) / Arizona State University (Publisher)
Created2023
Description
This thesis presents a study on the fuzzing of Linux binaries to find occluded bugs. Fuzzing is a widely-used technique for identifying software bugs. Despite their effectiveness, state-of-the-art fuzzers suffer from limitations in efficiency and effectiveness. Fuzzers based on random mutations are fast but struggle to generate high-quality inputs. In contrast, fuzzers based on symbolic execution produce quality inputs but lack execution speed. This paper proposes FlakJack, a novel hybrid fuzzer that patches the binary on the go to detect occluded bugs guarded by surface bugs. To dynamically overcome the challenge of patching binaries, the paper introduces multiple patching strategies based on the type of bug detected. The performance of FlakJack was evaluated on ten widely-used real-world binaries and one chaff dataset binary. The results indicate that many bugs found recently were already present in previous versions but were occluded by surface bugs. FlakJack’s approach improved the bug-finding ability by patching surface bugs that usually guard occluded bugs, significantly reducing patching cycles. Despite its unbalanced approach compared to other coverage-guided fuzzers, FlakJack is fast, lightweight, and robust. False- Positives can be filtered out quickly, and the approach is practical in other parts of the target. The paper shows that the FlakJack approach can significantly improve fuzzing performance without relying on complex strategies.
ContributorsPraveen Menon, Gokulkrishna (Author) / Bao, Tiffany (Thesis advisor) / Shoshitaishvili, Yan (Thesis advisor) / Doupe, Adam (Committee member) / Arizona State University (Publisher)
Created2023
Description
Reverse engineering is a process focused on gaining an understanding for the intricaciesof a system. This practice is critical in cybersecurity as it promotes the
findings and patching of vulnerabilities as well as the counteracting of malware. Disassemblers
and decompilers have become essential when reverse engineering due to
the readability of information they transcribe from binary files. However, these tools
still tend to produce involved and complicated outputs that hinder the acquisition of
knowledge during binary analysis. Cognitive Load Theory (CLT) explains that this
hindrance is due to the human brain’s inability to process superfluous amounts of
data. CLT classifies this data into three cognitive load types — intrinsic, extraneous,
and germane — that each can help gauge complex procedures.
In this research paper, a novel program call graph is presented accounting for
these CLT principles. The goal of this graphical view is to reduce the cognitive load
tied to the depiction of binary information and to enhance the overall binary analysis
process. This feature was implemented within the binary analysis tool, angr and it’s
user interface counterpart, angr-management. Additionally, this paper will examine a
conducted user study to quantitatively and qualitatively evaluate the effectiveness of
the newly proposed proximity view (PV). The user study includes a binary challenge
solving portion measured by defined metrics and a survey phase to receive direct participant
feedback regarding the view. The results from this study show statistically
significant evidence that PV aids in challenge solving and improves the overall understanding
binaries. The results also signify that this improvement comes with the
cost of time. The survey section of the user study further indicates that users find
PV beneficial to the reverse engineering process, but additional information needs to
be included in future developments.
ContributorsSmits, Sean (Author) / Wang, Ruoyu (Thesis advisor) / Shoshitaishvili, Yan (Thesis advisor) / Doupe, Adam (Committee member) / Arizona State University (Publisher)
Created2022
Description
Binary analysis and software debugging are critical tools in the modern softwaresecurity ecosystem. With the security arms race between attackers discovering and
exploiting vulnerabilities and the development teams patching bugs ever-tightening,
there is an immense need for more tooling to streamline the binary analysis and
debugging processes. Whether attempting to find the root cause for a buffer overflow
or a segmentation fault, the analysis process often involves manually tracing the
movement of data throughout a program’s life cycle. Up until this point, there has
not been a viable solution to the human limitation of maintaining a cohesive mental
image of the intricacies of a program’s data flow.
This thesis proposes a novel data dependency graph (DDG) analysis as an addi-
tion to angr’s analyses suite. This new analysis ingests a symbolic execution trace
in order to generate a directed acyclic graph of the program’s data dependencies. In
addition to the development of the backend logic needed to generate this graph, an
angr management view to visualize the DDG was implemented. This user interface
provides functionality for ancestor and descendant dependency tracing and sub-graph
creation. To evaluate the analysis, a user study was conducted to measure the view’s
efficacy in regards to binary analysis and software debugging. The study consisted
of a control group and experimental group attempting to solve a series of 3 chal-
lenges and subsequently providing feedback concerning perceived functionality and
comprehensibility pertaining to the view.
The results show that the view had a positive trend in relation to challenge-solving
accuracy in its target domain, as participants solved 32% more challenges 21% faster
when using the analysis than when using vanilla angr management.
ContributorsCapuano, Bailey Kellen (Author) / Shoshitaishvili, Yan (Thesis advisor) / Wang, Ruoyu (Thesis advisor) / Doupe, Adam (Committee member) / Arizona State University (Publisher)
Created2022
Description
Studies on underground forums can significantly advance the understanding of cybercrime workflow and underground economies. However, research on underground forums has concentrated on public information with little attention paid to users’ private interactions. Since detailed information will be discussed privately, the failure to investigate private interactions may miss critical intelligence and even misunderstand the entire underground economy. Furthermore, underground forums have evolved into criminal freelance markets where criminals trade illicit products and cybercrime services, allowing unsophisticated people to launch sophisticated cyber attacks. However, current research rarely examines and explores how criminals interact with each other, which makes researchers miss the opportunities to detect new cybercrime patterns proactively. Moreover, in clearnet, criminals are active in exploiting human vulnerabilities to conduct various attacks, and the phishing attack is one of the most prevalent types of cybercrime. Phishing awareness training has been proven to decrease the rate of clicking phishing emails. However, the rate of reporting phishing attacks is unexpectedly low based on recent studies, leaving phishing websites with hours of additional active time before being detected. In this dissertation, I first present an analysis of private interactions in underground forums and introduce machine learning-based approaches to detect hidden connections between users. Secondly, I analyze how criminals collaborate with each other in an emerging scam service in underground forums that exploits the return policies of merchants to get a refund or a replacement without returning the purchased products. Finally, I conduct a comprehensive evaluation of the phishing reporting ecosystem to identify the critical challenges while reporting phishing attacks to enable people to fight against phishers proactively.
ContributorsSun, Zhibo (Author) / Ahn, Gail-Joon (Thesis advisor) / Doupe, Adam (Thesis advisor) / Bao, Tiffany (Committee member) / Benjamin, Victor (Committee member) / Arizona State University (Publisher)
Created2022