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- All Subjects: Computer Science
- Creators: Doupe, Adam
Description
The ease of programmability in Software-Defined Networking (SDN) makes it a great platform for implementation of various initiatives that involve application deployment, dynamic topology changes, and decentralized network management in a multi-tenant data center environment. However, implementing security solutions in such an environment is fraught with policy conflicts and consistency issues with the hardness of this problem being affected by the distribution scheme for the SDN controllers.
In this dissertation, a formalism for flow rule conflicts in SDN environments is introduced. This formalism is realized in Brew, a security policy analysis framework implemented on an OpenDaylight SDN controller. Brew has comprehensive conflict detection and resolution modules to ensure that no two flow rules in a distributed SDN-based cloud environment have conflicts at any layer; thereby assuring consistent conflict-free security policy implementation and preventing information leakage. Techniques for global prioritization of flow rules in a decentralized environment are presented, using which all SDN flow rule conflicts are recognized and classified. Strategies for unassisted resolution of these conflicts are also detailed. Alternately, if administrator input is desired to resolve conflicts, a novel visualization scheme is implemented to help the administrators view the conflicts in an aesthetic manner. The correctness, feasibility and scalability of the Brew proof-of-concept prototype is demonstrated. Flow rule conflict avoidance using a buddy address space management technique is studied as an alternate to conflict detection and resolution in highly dynamic cloud systems attempting to implement an SDN-based Moving Target Defense (MTD) countermeasures.
In this dissertation, a formalism for flow rule conflicts in SDN environments is introduced. This formalism is realized in Brew, a security policy analysis framework implemented on an OpenDaylight SDN controller. Brew has comprehensive conflict detection and resolution modules to ensure that no two flow rules in a distributed SDN-based cloud environment have conflicts at any layer; thereby assuring consistent conflict-free security policy implementation and preventing information leakage. Techniques for global prioritization of flow rules in a decentralized environment are presented, using which all SDN flow rule conflicts are recognized and classified. Strategies for unassisted resolution of these conflicts are also detailed. Alternately, if administrator input is desired to resolve conflicts, a novel visualization scheme is implemented to help the administrators view the conflicts in an aesthetic manner. The correctness, feasibility and scalability of the Brew proof-of-concept prototype is demonstrated. Flow rule conflict avoidance using a buddy address space management technique is studied as an alternate to conflict detection and resolution in highly dynamic cloud systems attempting to implement an SDN-based Moving Target Defense (MTD) countermeasures.
ContributorsPisharody, Sandeep (Author) / Huang, Dijiang (Thesis advisor) / Ahn, Gail-Joon (Committee member) / Syrotiuk, Violet (Committee member) / Doupe, Adam (Committee member) / Arizona State University (Publisher)
Created2017
Description
The volume and frequency of cyber attacks have exploded in recent years. Organizations subscribe to multiple threat intelligence feeds to increase their knowledge base and better equip their security teams with the latest information in threat intelligence domain. Though such subscriptions add intelligence and can help in taking more informed decisions, organizations have to put considerable efforts in facilitating and analyzing a large number of threat indicators. This problem worsens further, due to a large number of false positives and irrelevant events detected as threat indicators by existing threat feed sources. It is often neither practical nor cost-effective to analyze every single alert considering the staggering volume of indicators. The very reason motivates to solve the overcrowded threat indicators problem by prioritizing and filtering them.
To overcome above issue, I explain the necessity of determining how likely a reported indicator is malicious given the evidence and prioritizing it based on such determination. Confidence Score Measurement system (CSM) introduces the concept of confidence score, where it assigns a score of being malicious to a threat indicator based on the evaluation of different threat intelligence systems. An indicator propagates maliciousness to adjacent indicators based on relationship determined from behavior of an indicator. The propagation algorithm derives final confidence to determine overall maliciousness of the threat indicator. CSM can prioritize the indicators based on confidence score; however, an analyst may not be interested in the entire result set, so CSM narrows down the results based on the analyst-driven input. To this end, CSM introduces the concept of relevance score, where it combines the confidence score with analyst-driven search by applying full-text search techniques. It prioritizes the results based on relevance score to provide meaningful results to the analyst. The analysis shows the propagation algorithm of CSM linearly scales with larger datasets and achieves 92% accuracy in determining threat indicators. The evaluation of the result demonstrates the effectiveness and practicality of the approach.
To overcome above issue, I explain the necessity of determining how likely a reported indicator is malicious given the evidence and prioritizing it based on such determination. Confidence Score Measurement system (CSM) introduces the concept of confidence score, where it assigns a score of being malicious to a threat indicator based on the evaluation of different threat intelligence systems. An indicator propagates maliciousness to adjacent indicators based on relationship determined from behavior of an indicator. The propagation algorithm derives final confidence to determine overall maliciousness of the threat indicator. CSM can prioritize the indicators based on confidence score; however, an analyst may not be interested in the entire result set, so CSM narrows down the results based on the analyst-driven input. To this end, CSM introduces the concept of relevance score, where it combines the confidence score with analyst-driven search by applying full-text search techniques. It prioritizes the results based on relevance score to provide meaningful results to the analyst. The analysis shows the propagation algorithm of CSM linearly scales with larger datasets and achieves 92% accuracy in determining threat indicators. The evaluation of the result demonstrates the effectiveness and practicality of the approach.
ContributorsModi, Ajay (Author) / Ahn, Gail-Joon (Thesis advisor) / Zhao, Ziming (Committee member) / Doupe, Adam (Committee member) / Arizona State University (Publisher)
Created2017
Description
Today the information technology systems have addresses, software stacks and other configuration remaining unchanged for a long period of time. This paves way for malicious attacks in the system from unknown vulnerabilities. The attacker can take advantage of this situation and plan their attacks with sufficient time. To protect our system from this threat, Moving Target Defense is required where the attack surface is dynamically changed, making it difficult to strike.
In this thesis, I incorporate live migration of Docker container using CRIU (checkpoint restore) for moving target defense. There are 460K Dockerized applications, a 3100% growth over 2 years[1]. Over 4 billion containers have been pulled so far from Docker hub. Docker is supported by a large and fast growing community of contributors and users. As an example, there are 125K Docker Meetup members worldwide. As we see industry adapting to Docker rapidly, a moving target defense solution involving containers is beneficial for being robust and fast. A proof of concept implementation is included for studying performance attributes of Docker migration.
The detection of attack is using a scenario involving definitions of normal events on servers. By defining system activities, and extracting syslog in centralized server, attack can be detected via extracting abnormal activates and this detection can be a trigger for the Docker migration.
In this thesis, I incorporate live migration of Docker container using CRIU (checkpoint restore) for moving target defense. There are 460K Dockerized applications, a 3100% growth over 2 years[1]. Over 4 billion containers have been pulled so far from Docker hub. Docker is supported by a large and fast growing community of contributors and users. As an example, there are 125K Docker Meetup members worldwide. As we see industry adapting to Docker rapidly, a moving target defense solution involving containers is beneficial for being robust and fast. A proof of concept implementation is included for studying performance attributes of Docker migration.
The detection of attack is using a scenario involving definitions of normal events on servers. By defining system activities, and extracting syslog in centralized server, attack can be detected via extracting abnormal activates and this detection can be a trigger for the Docker migration.
ContributorsBohara, Bhakti (Author) / Huang, Dijiang (Thesis advisor) / Doupe, Adam (Committee member) / Zhao, Ziming (Committee member) / Arizona State University (Publisher)
Created2017
Description
Mobile telephony is a critical aspect of our modern society: through telephone calls,
it is possible to reach almost anyone around the globe. However, every mobile telephone
call placed implicitly leaks the user's location to the telephony service provider (TSP).
This privacy leakage is due to the fundamental nature of mobile telephony calls that
must connect to a local base station to receive service and place calls. Thus, the TSP
can track the physical location of the user for every call that they place. While the
The Internet is similar in this regard, privacy-preserving technologies such as Tor allow
users to connect to websites anonymously (without revealing to their ISP the site
that they are visiting). In this thesis, the scheme presented, called shadow calling,
to allow geolocation anonymous calling from legacy mobile devices. In this way,
the call is placed from the same number, however, the TSP will not know the user's
physical location. The scheme does not require any change on the network side and
can be used on current mobile networks. The scheme implemented is for the GSM
(commonly referred to as 2G) network, as it is the most widely used mode of mobile
telephony communication. The feasibility of our scheme is demonstrated through the
prototype. Shadow calling, which renders the users geolocation anonymous, will be
beneficial for users such as journalists, human rights activists in hostile nations, or
other privacy-demanding users.
it is possible to reach almost anyone around the globe. However, every mobile telephone
call placed implicitly leaks the user's location to the telephony service provider (TSP).
This privacy leakage is due to the fundamental nature of mobile telephony calls that
must connect to a local base station to receive service and place calls. Thus, the TSP
can track the physical location of the user for every call that they place. While the
The Internet is similar in this regard, privacy-preserving technologies such as Tor allow
users to connect to websites anonymously (without revealing to their ISP the site
that they are visiting). In this thesis, the scheme presented, called shadow calling,
to allow geolocation anonymous calling from legacy mobile devices. In this way,
the call is placed from the same number, however, the TSP will not know the user's
physical location. The scheme does not require any change on the network side and
can be used on current mobile networks. The scheme implemented is for the GSM
(commonly referred to as 2G) network, as it is the most widely used mode of mobile
telephony communication. The feasibility of our scheme is demonstrated through the
prototype. Shadow calling, which renders the users geolocation anonymous, will be
beneficial for users such as journalists, human rights activists in hostile nations, or
other privacy-demanding users.
ContributorsPinto, Gerard Lawrence (Author) / Doupe, Adam (Thesis advisor) / Ahn, Gail-Joon (Committee member) / Zhao, Ziming (Committee member) / Arizona State University (Publisher)
Created2017
Description
Web applications are an incredibly important aspect of our modern lives. Organizations
and developers use automated vulnerability analysis tools, also known as
scanners, to automatically find vulnerabilities in their web applications during development.
Scanners have traditionally fallen into two types of approaches: black-box
and white-box. In the black-box approaches, the scanner does not have access to the
source code of the web application whereas a white-box approach has access to the
source code. Today’s state-of-the-art black-box vulnerability scanners employ various
methods to fuzz and detect vulnerabilities in a web application. However, these
scanners attempt to fuzz the web application with a number of known payloads and
to try to trigger a vulnerability. This technique is simple but does not understand
the web application that it is testing. This thesis, presents a new approach to vulnerability
analysis. The vulnerability analysis module presented uses a novel approach
of Inductive Reverse Engineering (IRE) to understand and model the web application.
IRE first attempts to understand the behavior of the web application by giving
certain number of input/output pairs to the web application. Then, the IRE module
hypothesizes a set of programs (in a limited language specific to web applications,
called AWL) that satisfy the input/output pairs. These hypotheses takes the form of
a directed acyclic graph (DAG). AWL vulnerability analysis module can then attempt
to detect vulnerabilities in this DAG. Further, it generates the payload based on the
DAG, and therefore this payload will be a precise payload to trigger the potential vulnerability
(based on our understanding of the program). It then tests this potential
vulnerability using the generated payload on the actual web application, and creates
a verification procedure to see if the potential vulnerability is actually vulnerable,
based on the web application’s response.
and developers use automated vulnerability analysis tools, also known as
scanners, to automatically find vulnerabilities in their web applications during development.
Scanners have traditionally fallen into two types of approaches: black-box
and white-box. In the black-box approaches, the scanner does not have access to the
source code of the web application whereas a white-box approach has access to the
source code. Today’s state-of-the-art black-box vulnerability scanners employ various
methods to fuzz and detect vulnerabilities in a web application. However, these
scanners attempt to fuzz the web application with a number of known payloads and
to try to trigger a vulnerability. This technique is simple but does not understand
the web application that it is testing. This thesis, presents a new approach to vulnerability
analysis. The vulnerability analysis module presented uses a novel approach
of Inductive Reverse Engineering (IRE) to understand and model the web application.
IRE first attempts to understand the behavior of the web application by giving
certain number of input/output pairs to the web application. Then, the IRE module
hypothesizes a set of programs (in a limited language specific to web applications,
called AWL) that satisfy the input/output pairs. These hypotheses takes the form of
a directed acyclic graph (DAG). AWL vulnerability analysis module can then attempt
to detect vulnerabilities in this DAG. Further, it generates the payload based on the
DAG, and therefore this payload will be a precise payload to trigger the potential vulnerability
(based on our understanding of the program). It then tests this potential
vulnerability using the generated payload on the actual web application, and creates
a verification procedure to see if the potential vulnerability is actually vulnerable,
based on the web application’s response.
ContributorsKhairnar, Tejas (Author) / Doupe, Adam (Thesis advisor) / Ahn, Gail-Joon (Committee member) / Zhao, Ziming (Committee member) / Arizona State University (Publisher)
Created2017
Description
Field of cyber threats is evolving rapidly and every day multitude of new information about malware and Advanced Persistent Threats (APTs) is generated in the form of malware reports, blog articles, forum posts, etc. However, current Threat Intelligence (TI) systems have several limitations. First, most of the TI systems examine and interpret data manually with the help of analysts. Second, some of them generate Indicators of Compromise (IOCs) directly using regular expressions without understanding the contextual meaning of those IOCs from the data sources which allows the tools to include lot of false positives. Third, lot of TI systems consider either one or two data sources for the generation of IOCs, and misses some of the most valuable IOCs from other data sources.
To overcome these limitations, we propose iGen, a novel approach to fully automate the process of IOC generation and analysis. Proposed approach is based on the idea that our model can understand English texts like human beings, and extract the IOCs from the different data sources intelligently. Identification of the IOCs is done on the basis of the syntax and semantics of the sentence as well as context words (e.g., ``attacked'', ``suspicious'') present in the sentence which helps the approach work on any kind of data source. Our proposed technique, first removes the words with no contextual meaning like stop words and punctuations etc. Then using the rest of the words in the sentence and output label (IOC or non-IOC sentence), our model intelligently learn to classify sentences into IOC and non-IOC sentences. Once IOC sentences are identified using this learned Convolutional Neural Network (CNN) based approach, next step is to identify the IOC tokens (like domains, IP, URL) in the sentences. This CNN based classification model helps in removing false positives (like IPs which are not malicious). Afterwards, IOCs extracted from different data sources are correlated to find the links between thousands of apparently unrelated attack instances, particularly infrastructures shared between them. Our approach fully automates the process of IOC generation from gathering data from different sources to creating rules (e.g. OpenIOC, snort rules, STIX rules) for deployment on
the security infrastructure.
iGen has collected around 400K IOCs till now with a precision of 95\%, better than any state-of-art method.
To overcome these limitations, we propose iGen, a novel approach to fully automate the process of IOC generation and analysis. Proposed approach is based on the idea that our model can understand English texts like human beings, and extract the IOCs from the different data sources intelligently. Identification of the IOCs is done on the basis of the syntax and semantics of the sentence as well as context words (e.g., ``attacked'', ``suspicious'') present in the sentence which helps the approach work on any kind of data source. Our proposed technique, first removes the words with no contextual meaning like stop words and punctuations etc. Then using the rest of the words in the sentence and output label (IOC or non-IOC sentence), our model intelligently learn to classify sentences into IOC and non-IOC sentences. Once IOC sentences are identified using this learned Convolutional Neural Network (CNN) based approach, next step is to identify the IOC tokens (like domains, IP, URL) in the sentences. This CNN based classification model helps in removing false positives (like IPs which are not malicious). Afterwards, IOCs extracted from different data sources are correlated to find the links between thousands of apparently unrelated attack instances, particularly infrastructures shared between them. Our approach fully automates the process of IOC generation from gathering data from different sources to creating rules (e.g. OpenIOC, snort rules, STIX rules) for deployment on
the security infrastructure.
iGen has collected around 400K IOCs till now with a precision of 95\%, better than any state-of-art method.
ContributorsPanwar, Anupam (Author) / Ahn, Gail-Joon (Thesis advisor) / Doupe, Adam (Committee member) / Zhao, Ziming (Committee member) / Arizona State University (Publisher)
Created2017
Description
The omnipresent data, growing number of network devices, and evolving attack techniques have been challenging organizations’ security defenses over the past decade. With humongous volumes of logs generated by those network devices, looking for patterns of malicious activities and identifying them in time is growing beyond the capabilities of their defense systems. Deep Learning, a subset of Machine Learning (ML) and Artificial Intelligence (AI), fills in this gapwith its ability to learn from huge amounts of data, and improve its performance as the data it learns from increases. In this dissertation, I bring forward security issues pertaining to two top threats that most organizations fear, Advanced Persistent Threat (APT), and Distributed Denial of Service (DDoS), along with deep learning models built towards addressing those
security issues. First, I present a deep learning model, APT Detection, capable of detecting anomalous activities in a system. Evaluation of this model demonstrates how it can contribute to early detection of an APT attack with an Area Under the Curve (AUC) of up to 91% on a Receiver Operating Characteristic (ROC) curve. Second, I present DAPT2020, a first of its kind dataset capturing an APT attack exploiting web and system vulnerabilities in an emulated organization’s production network. Evaluation of the dataset using well known machine learning models demonstrates the need for better deep learning models to detect APT attacks. I then present DAPT2021, a semi-synthetic dataset capturing an APT attackexploiting human vulnerabilities, alongside 2 less skilled attacks. By emulating the normal behavior of the employees in a set target organization, DAPT2021 has been created to enable researchers study the causations and correlations among the captured data, a much-needed information to detect an underlying threat early. Finally, I present a distributed defense
framework, SmartDefense, that can detect and mitigate over 90% of DDoS traffic at the source and over 97.5% of the remaining DDoS traffic at the Internet Service Provider’s (ISP’s) edge network. Evaluation of this work shows how by using attributes sent by customer edge network, SmartDefense can further help ISPs prevent up to 51.95% of the DDoS traffic
from going to the destination.
ContributorsMyneni, Sowmya (Author) / Xue, Guoliang (Thesis advisor) / Doupe, Adam (Committee member) / Li, Baoxin (Committee member) / Baral, Chitta (Committee member) / Arizona State University (Publisher)
Created2022
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
As computers and the Internet have become integral to daily life, the potential gains from exploiting these resources have increased significantly. The global landscape is now rife with highly skilled wrongdoers seeking to steal from and disrupt society. In order to safeguard society and its infrastructure, a comprehensive approach to research is essential. This work aims to enhance security from three unique viewpoints by expanding the resources available to educators, users, and analysts. For educators, a capture the flag as-a-service was developed to support cybersecurity education. This service minimizes the skill and time needed to establish the infrastructure for hands-on hacking experiences for cybersecurity students. For users, a tool called CloakX was created to improve online anonymity. CloakX prevents the identification of browser extensions by employing both static and dynamic rewriting techniques, thwarting contemporary methods of detecting installed extensions and thus protecting user identity. Lastly, for cybersecurity analysts, a tool named Witcher was developed to automate the process of crawling and exercising web applications while identifying web injection vulnerabilities. Overall, these contributions serve to strengthen security education, bolster privacy protection for users, and facilitate vulnerability discovery for cybersecurity analysts.
ContributorsTrickel, Erik (Author) / Doupe, Adam (Thesis advisor) / Shoshitaishvili, Yan (Thesis advisor) / Bao, Tiffany (Committee member) / Wang, Ruoyu (Committee member) / Arizona State University (Publisher)
Created2023
Description
For systems having computers as a significant component, it becomes a critical task to identify the potential threats that the users of the system can present, while being both inside and outside the system. One of the most important factors that differentiate an insider from an outsider is the fact that the insider being a part of the system, owns privileges that enable him/her access to the resources and processes of the system through valid capabilities. An insider with malicious intent can potentially be more damaging compared to outsiders. The above differences help to understand the notion and scope of an insider.
The significant loss to organizations due to the failure to detect and mitigate the insider threat has resulted in an increased interest in insider threat detection. The well-studied effective techniques proposed for defending against attacks by outsiders have not been proven successful against insider attacks. Although a number of security policies and models to deal with the insider threat have been developed, the approach taken by most organizations is the use of audit logs after the attack has taken place. Such approaches are inspired by academic research proposals to address the problem by tracking activities of the insider in the system. Although tracking and logging are important, it is argued that they are not sufficient. Thus, the necessity to predict the potential damage of an insider is considered to help build a stronger evaluation and mitigation strategy for the insider attack. In this thesis, the question that seeks to be answered is the following: `Considering the relationships that exist between the insiders and their role, their access to the resources and the resource set, what is the potential damage that an insider can cause?'
A general system model is introduced that can capture general insider attacks including those documented by Computer Emergency Response Team (CERT) for the Software Engineering Institute (SEI). Further, initial formulations of the damage potential for leakage and availability in the model is introduced. The model usefulness is shown by expressing 14 of actual attacks in the model and show how for each case the attack could have been mitigated.
The significant loss to organizations due to the failure to detect and mitigate the insider threat has resulted in an increased interest in insider threat detection. The well-studied effective techniques proposed for defending against attacks by outsiders have not been proven successful against insider attacks. Although a number of security policies and models to deal with the insider threat have been developed, the approach taken by most organizations is the use of audit logs after the attack has taken place. Such approaches are inspired by academic research proposals to address the problem by tracking activities of the insider in the system. Although tracking and logging are important, it is argued that they are not sufficient. Thus, the necessity to predict the potential damage of an insider is considered to help build a stronger evaluation and mitigation strategy for the insider attack. In this thesis, the question that seeks to be answered is the following: `Considering the relationships that exist between the insiders and their role, their access to the resources and the resource set, what is the potential damage that an insider can cause?'
A general system model is introduced that can capture general insider attacks including those documented by Computer Emergency Response Team (CERT) for the Software Engineering Institute (SEI). Further, initial formulations of the damage potential for leakage and availability in the model is introduced. The model usefulness is shown by expressing 14 of actual attacks in the model and show how for each case the attack could have been mitigated.
ContributorsNolastname, Sharad (Author) / Bazzi, Rida (Thesis advisor) / Sen, Arunabha (Committee member) / Doupe, Adam (Committee member) / Arizona State University (Publisher)
Created2019