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Digital forensics for Investigating Control-logic Attacks in Industrial Control Systems
Get PDFProgrammable logic controllers (PLC) are required to handle physical processes and thus crucial in critical infrastructures like power grids, nuclear facilities, and gas pipelines. Attacks on PLCs can have disastrous consequences, considering attacks like Stuxnet and TRISIS. Those attacks are examples of exploits where the attacker aims to inject into a target PLC malicious control logic, which engineering software compiles as a reliable code. When investigating a security incident, acquiring memory can provide valuable insight such as runtime system activities and memory-based artifacts which may contain the attacker\u27s footprints. The existing memory acquisition tools for PLCs require a hardware-level debugging port or network protocol-based approaches, which are not practical in the real world or provide partial acquisition of memory.
This research work provides an overview of different attacks on PLCs. This work shows what embodies these three different approaches. These novel approaches leaves PLCs vulnerable that can unleash mayhem in the physical world.
The first approach describes denial of engineering operations (DEO) attacks in industrial control systems, referred to as a denial of decompilation (DoD) attack. The DoD attack involves obfuscating and installing a (malicious) control logic into a programmable logic controller (PLC) to fail the decompilation function in engineering software required to maintain control logic in PLCs. The existing seminal work on the DEO attacks exploits engineering software\u27s improper input validation vulnerability. On the other hand, the DoD attack targets a fundamental design principle in compiling and decompiling control logic in engineering software, thereby affecting the engineering software of multiple vendors. We evaluate the DoD attack on two major PLC manufacturers\u27 PLCs, i.e., Schneider Electric Modicon M221 and Siemens S7-300. We show that simple obfuscation techniques on control logic are sufficient to compromise the decompilation function in their engineering software, i.e., SoMachine Basic and TIA Portal, respectively.
The second approach propose two control-logic attacks and a new memory acquisition framework for PLCs. The first attack modifies in-memory firmware such that the attacker takes control of a PLC\u27s built-in functions. The second attack involves obfuscating and installing a malicious control logic into a target PLC to fail the decompilation process in engineering software. The proposed memory acquisition framework remotely acquires a PLC\u27s volatile memory while the PLC is controlling a physical process. The main idea is to inject a harmless code that essentially copies the protected memory fragments to protocol-mapped memory space, which is acquirable over the network. Since the proposed memory acquisition allows access to the entire memory, we can also show the evidence of the attacks.
The third approach propose an attack which doesn\u27t involve alteration or injection of PLC\u27s control logic. Return Oriented Programming(ROP) is an exploiting technique which can perform sophisticated attacks by utilizing the existing code in the memory of the PLC. This attack doesn\u27t involves injecting code which makes this technique unique and hard to discover. This work is the first attempt to introduce ROP attack technique successfully on PLC without disrupting the control logic cycle.
We evaluate the proposed methods on a gas pipeline testbed to demonstrate the attacks and how a forensic investigator can identify the attacks and other critical forensic artifacts using the proposed memory acquisition method
Optimization Framework to Determine Optimal Location and Sizing of Photovoltaic Energy Sources in Electric Grids
Get PDFThe purpose of this thesis is the presentation of a methodology for determining the optimal location and size of Photovoltaic (PV) renewable energy sources for integration to power systems. The proposed methodology is based on applying Particle Swarm Optimization (PSO) in determining the optimal location and size of PV energy sources by minimizing real power loss as the objective (cost) the function of the optimization and voltage magnitude limits, eigenvalues of the Jacobian matrix, and transmission line and transformer overloads as the optimization constraints and is scalable for the inclusion of reactive power losses and fuel costs in the objective function and power system security measures as constraints. The optimal size and location of PV energy sources are determined by implementing the proposed framework for studying real size power systems and is used in simulating test systems in their steady-state and dynamic mode of operation. The proposed methodology is used to simulate the IEEE 14 and 39 bus systems by using MatLab, PowerWorld, and PSS/E as simulation tools
Synthesis of Inorganic-Organic Perovskite Hybrid Materials via a Microwave Assisted Method
Get PDFThe research presented here focusses on fabrication of organic modified inorganic two-dimensional and three-dimensional materials via microwave assisted methods. These hybrid materials are of importance due to their capacity to incorporate the characteristics of both organic and inorganic components. Microwave methods have been utilized to expedite the topochemical modification of layered perovskites. In one set of studies, microwave assisted grafting reactions were performed on layered perovskite (HLaNb2O7) materials with a series of hydroxy carboxylic acids. The reactivities of these organic compounds with the layered perovskites and the influence of precursor, temperature and time are demonstrated. The hydroxy carboxylic acid grafted perovskites show interesting optical properties which were investigated using UV-Vis spectroscopy. In addition to inorganic-organic perovskite fabrication, an exfoliation-restacking procedure was performed on double and triple layered Dion-Jacobson phases (HLaNb2O7 and HCa2Nb3O10 respectively). Homogenous and heterogenous restacking procedures were performed and then compared with constructed models. Apart from grafting with hydroxy carboxylic acids, surface modification of Dion-Jacobson phases using a diol (hydroquinone) were performed on two-dimensional nanosheets and three-dimensional layered materials using both microwave and benchtop methods. The inorganic-organic hybrid materials investigated are demonstrated to have bilayer arrangement in the interlayer. Furthermore, structural refinement of HLaNb2O7 was performed using neutron diffraction data to identify the position of hydrogen in the interlayer
Climate Change and Urban Tourism: Preservation Strategies and Destination Management Policies in Coastal Cities. The Case of Venice
Get PDFClimate change is an influencing phenomenon in the present global perspective, having a wide range of impacts at different levels within society and the global tourism industry. Climate change has progressively affected coastal areas more vulnerable to intense hydrodynamic and atmospheric events due to their proximity to water. The primary process to be held responsible is eustatic sea-level rise due to anthropogenic (human-induced) and morphological (natural) factors over time. While the exact magnitude of global sea-level rise and regional variability remains uncertain, sea-level rise is considered one of the most certain consequences of anthropogenic climate change in the coastal regions that rely on tourism activities. Tourism has a more significant environmental impact on coastal areas than non-coastal areas due to its proximity to water and cruise line activities. This research presents a case study on Venice. In this emblematic iconic city, the two most pressing issues are flooding due to sea-level rise and locals fleeing the city due to the overtourism phenomena. The research uses a mixed methods approach to examine changes adopted to manage climate change stressors and overtourism activities in Venice to ensure the city’s habitability by 2100. The research uses the conceptual framework between environmental impact and urban tourism as a reference and develops a framework that includes socio-cultural and economic impacts at the destination level. In addition to its proximity to water, Venice is characterized by a strong economic dependence on the tourism and hospitality industry, leading the research to examine how the industry (alongside climate patterns) affects a UNESCO world heritage site’s historical heritage and cultural preservation over the past 20 years, and what actions are required to protect Venice in the future.
This study contributes to the tourism and climate change body of knowledge by advancing a further step toward understanding experts’ and tourism stakeholders’ responses to the safeguarding of Venice in a scenario in which a destination’s most appealing, cultural, historical, and natural resources are impacted by climate change
Directing a Contemporary Deconstruction of a Chekhov Play
Get PDFWhen examining Stupid Fucking Bird, it is important to recognize that it is a deconstructed adaptation of Chekhov’s The Seagull. Aaron Posner’s, Stupid Fucking Bird, shakes up Chekhov’s old form with something new and, perhaps, more relevant than its original form. The thesis includes a detailed analysis of the production process and post-production analysis of Stupid Fucking Bird written by Aaron Posner and directed by Margaret Tonra at UNO, October 2021-February 2022
Additive Manufacturing of Variable Contrast Computed Tomography Anatomical Phantoms Using a Single Feedstock in Fused Filament Fabrication
Get PDFAnatomical phantoms used in biomedical education and training benefit greatly from Fused filament fabrication’s (FFF) ability to rapidly produce complex and unique models. Current materials and methods used in FFF have limited ability to accurately produce phantoms that can mimic the radiological properties of multiple biological tissues. This research demonstrates that the CT contrast of FFF produced models can be modified by varying the concentration of bismuth oxide in acrylonitrile butadiene styrene (ABS) filaments and a tunable CT contrast that mimics the CT contrast ranging from fatty tissue to cortical bone using a single composite filament without introducing artificial image artifacts is achieved by modifying the deposited filament structure using a rectilinear infill pattern with alternating solid layers. In addition, a method is demonstrated to produce a lumbar spine phantom with the infill modified to accurately mimic the CT contrast for the trabecular and cortical bone volumes of the model
“We Won’t Be Silent Anymore”: Enslaved People’s Stories and Symbolic Reparations For New Orleans City Park
Get PDFThe official history of New Orleans City Park, published in 1982 offers a narrow history of its grounds and land ownership before it opened as a park in 1854. The published text Historic City Park New Orleans contains a two-part narrative. The first narrative tells the identity of Louis Allard, his plantation land, and the mystique surrounding his death. The second narrative focuses on John McDonogh, an enslaver and local legend, his purchase of the Allard Plantation, and his donation of the plantation to the city of New Orleans for the creation of what is now lower New Orleans City Park. This official history obscures the actual history of City Park and its extensive plantations along Bayou St. John. It also excludes any mention of the enslaved men and women who lived and labored within the Allard Plantation or any other portion of the park grounds. This thesis uncovers the fourteen plantations that once occupied City Park grounds: the Allard, Roquigui, Girardy, DesRuisseaux, Milne, Jung, Lorreins, Alpuente, Castillon, Dugué, Zamora, St. Maxent, Almonester, and Morant. Through colonial documents, auction receipts, bills of sales, and court cases, this thesis lays the ground work for an ongoing public history project which will tell the named and unnamed enslaved people related to each of these plantations. The final section focuses on how the City Park space can be interpreted by and for the public through educational outreach and re-memorialization. The goal of this thesis is to provide a more wholistic historical narrative to locals and visitors of City Park and to honor the lives of enslaved Indigenous, African, and African American people forced to labor on its grounds
“An eternity or two later”: Family of Choice in Elaine Castillo’s America Is Not The Heart
Get PDFMany of the challenges faced by environmental activists are issues of scale. How can vital changes be enacted and sustained over the necessarily long time scales of environmental restoration? Elaine Castillo’s America Is Not the Heart (2018) illuminates a possible avenue for activists engaged in environmental justice work. Parts of the book contains extensive flashbacks to Hero’s, the protagonist’s, time as part of a cadre of the New People’s Army in the Philippines during the Marcos dictatorship. Though the NPA is not strictly an environmental activist group, the organization takes their cues from queer ecofeminist frameworks and the intersections between class, gender and sexuality, and exploited landscapes. At these queer ecofeminist intersections, the NPA can be read a family of choice, as the group comprises several unrelated individuals who chose to live, work, and learn together, akin to a family. One particular aspect of familial relations that the NPA takes on is an attention to generational storytelling and knowledge inheritance. New members are encouraged to share their family legends, regional mythos, etc., to build up the cadre’s stores of knowledge. In this way, the group’s efforts can continue on, even if members leave or are forcefully removed. Family of choice structures are reflected in the small, daily choices on which these long-term changes are built, as Hero\u27s considerably smaller, quieter life after the NPA contains echoes of her life during the height of her activist work
