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Durch die Fortschritte im Bereich der Quantencomputer rückt der Zeitpunkt näher, dass Quantencomputer die bestehenden mathematischen Probleme lösen können, welche in den aktuellen Public-Key-Verschlüsselungsverfahren verwendet werden. Als Reaktion darauf wurde ein Standardisierungsprozess für quantensichere Public-Key-Verschlüsselungsverfahren gestartet. Diese Arbeit analysiert diese und vergleicht sie untereinander, um Stärken und Schwächen der einzelnen Verfahren aufzuzeigen.
On a regular basis, we hear of well-known online services that have been abused or compromised as a result of data theft. Because insecure applications jeopardize users' privacy as well as the reputation of corporations and organizations, they must be effectively secured from the outset of the development process. The limited expertise and experience of involved parties, such as web developers, is frequently cited as a cause of risky programs. Consequently, they rarely have a full picture of the security-related decisions that must be made, nor do they understand how these decisions affect implementation accurately.
The selection of tools and procedures that can best assist a certain situation in order to protect an application against vulnerabilities is a critical decision. Regardless of the level of security that results from adhering to security standards, these factors inadvertently result in web applications that are insufficiently secured. JavaScript is a language that is heavily relied on as a mainstream programming language for web applications with several new JavaScript frameworks being released every year.
JavaScript is used on both the server-side in web applications development and the client-side in web browsers as well.
However, JavaScript web programming is based on a programming style in which the application developer can, and frequently must, automatically integrate various bits of code from third parties. This potent combination has resulted in a situation today where security issues are frequently exploited. These vulnerabilities can compromise an entire server if left unchecked. Even though there are numerous ad hoc security solutions for web browsers, client-side attacks are also popular. The issue is significantly worse on the server side because the security technologies available for server-side JavaScript application frameworks are nearly non-existent.
Consequently, this thesis focuses on the server-side aspect of JavaScript; the development and evaluation of robust server-side security technologies for JavaScript web applications. There is a clear need for robust security technologies and security best practices in server-side JavaScript that allow fine-grained security.
However, more than ever, there is this requirement of reducing the associated risks without hindering the web application in its functionality.
This is the problem that will be tackled in this thesis: the development of secure security practices and robust security technologies for JavaScript web applications, specifically, on the server-side, that offer adequate security guarantees without putting too many constraints on their functionality.
As information technology continues to advance at a rapid speed around the world, new difficulties emerge. The growing number of organizational vulnerabilities is among the most important issues. Finding and mitigating vulnerabilities is critical in order to protect an organization’s environment from multiple attack vectors.
The study investigates and comprehends the complete vulnerability management process from the standpoint of the security officer job role, as well as potential improvements. Few strategies are used to achieve efficient mitigation and the de- velopment of a process for tracking and mitigating vulnerabilities. As a result, a qualitative study is conducted in which the objective is to create a proposed vulner- ability and risk management process, as well as to develop a system for analyzing and tracking vulnerabilities and presenting the vulnerabilities in a graphical dash- board format. This thesis’s data was gathered through an organized literature study as well as through the use of various web resources. We explored numerous ap- proaches to analyze the data, such as categorizing the vulnerabilities every 30, 60, and 90 days to see whether the vulnerabilities were reoccurring or new. According to our findings, tracking vulnerabilities can be advantageous for a security officer.
We come to the conclusion that if an organization has a proper vulnerability tracking system and vulnerability management process, it can aid security officers in having a better understanding of and making plans for reducing vulnerabilities. In terms of system patching and vulnerability remediation, it will also assist the security officer in identifying areas of weakness in the process. As a result, the suggested ways provide an alternate approach to managing and tracking vulnerabilities in an effective manner, although there is still a small area that needs additional analysis and research to make it even better.
Komplexe E-Commerce-Systeme müssen heutzutage immer schneller am Markt sein und sich an diesen anpassen. Dies wird durch SaaS-Services möglich, wodurch sich die Best-of-Breed-Lösungen einsetzen lassen. Der monolithische Ansatz der meisten E-Commerce-Systeme ist für diese Anwendungen nicht mehr geeignet. Abhilfe soll der Composable-Commerce-Ansatz schaffen. Für den Ansatz wird eine Integrationslösung benötigt. Ziel dieser Thesis ist es, Integrationslösungen zu evaluieren und mithilfe von Integration-Layer-Prototypen gegenüberzustellen. Es werden zwei Integrationslösungen ausgewählt, die als Prototyp implementiert werden. Für den ersten Prototypen wird Apache Camel in einem Spring-Boot-Server verwendet. Der zweite Prototyp setzt die AWS-eigenen Services für die Integration ein. Zum Schluss werden diese durch einen Last-Test auf ihre Performance geprüft.
An organized strategy to ensure the security of an organization is an information security management system. During various security crises, hazards, and breaches, this strategy aids an organization in maintaining the confidentiality, integrity, and accessibility of information. Organizations are getting ready to comply with information security management system criteria. Despite this, security concerns continue to plague ineffective controls, have poor connectivity, or cause a silo effect, which is a common cause. One of the causes is a low maturity model that is not synchronized with the organization’s business processes. For a higher level of maturity, it is best to evaluate the practices.
Different maturity models on information security and cyber security capacity, management processes, security controls, implementation level, and many more have already been developed by numerous international organizations, experts, and scholars. The present models, however, do not assess a particular organization's particular practices. The evaluation of the business process is frequently neglected because measurement requirements for models are typically more concentrated on examining specific elements. For this reason, it caused the maturity assessment to not be executed explicitly and broadly.
We developed an organizational information security maturity model, a combination of work of different maturity models currently existing. While making this model, we considered that any size or type of organization could use this model. The model considers the success elements of the information security management system when assessing the implementation's effectiveness. We employed a mixed-method strategy that included both qualitative and quantitative research. With the help of a questionnaire survey, we evaluated the previous research using a qualitative methodology. In the quantitative method, we'll figure out how mature the information security management system is now. The proposed model could be used to reduce security incidents by improving implementation gaps.
Due to the increasing aging of the population, the number of elderly people requiring care is growing in most European countries. However, the number of caregivers working in nursing homes and on daily care services is declining in countries like Germany or Italy. This limits the time for interpersonal communication. Furthermore, as a result of the Covid-19 pandemic, social distancing during contact restrictions became more important, causing an additional reduction of personal interaction. This social isolation can strongly increase emotional stress. Robotic assistance could contribute to addressing this challenge on three levels: (1) supporting caregivers to respond individually to the needs of patients and residents in nursing homes; (2) observing patients’ health and emotional state; (3) complying with high hygiene standards and minimizing human contact if required. To further the research on emotional aspects and the acceptance of robotic assistance in care, we conducted two studies where elderly participants interacted with the social robot Misa. Facial expression and voice analysis were used to identify and measure the emotional state of the participants during the interaction. While interpersonal contact plays a major role in elderly care, the findings reveal that robotic assistance generates added value for both caregivers and patients and that they show emotions while interacting with them.
Software-defined Access (SD-Access, SDA) hat aufgrund der flexiblen, automatisierten und schnelleren Verwaltung von Unternehmensnetzwerken erhebliche Aufmerksamkeit erlangt. Im Gegensatz zu traditionellen Netzwerken mit manuellen Prozessen, bietet SD-Access Zugriffsrichtlinien, Netzwerksegmentierung und Endpunktüberwachung in einer Lösung und trägt damit zur Netzwerksicherheit in Unternehmen bei.
Zunächst wird die SD-Access-Lösung von Cisco vorgestellt und herausgearbeitet, welche Komponenten dafür benötigt werden. Auf dieser Grundlage wird überprüft, welche Voraussetzungen zur Einführung von SD-Access im konkreten Anwendungsfall, dem SWR, geschaffen werden müssen.
Anschließend wird in einer experimentellen Phase im SWR-eigenen Netzwerklabor eine beispielhafte Architektur mit allen benötigten Komponenten zu Testzwecken konzeptioniert und implementiert. Dabei ist das Design und die Konfiguration möglichst nahe an der realen Umgebung des SWRs orientiert. Mit dem vorliegenden Testsetup werden dann bestimmte Funktionen und Anwendungsszenarien genauer aufgezeigt und die Relevanz für den Sicherheitsgewinn im SWR-LAN untersucht.
Darauf folgt eine abschließende Beurteilung des Sicherheits- und Effizienzgewinns durch die Einführung von SD-Access im SWR-Netzwerk.
This work addresses the conceptualization, design, and implementation of an Application Programming Interface (API) for the Common Security Advisory Framework (CSAF) 2.0, introducing another method for distributing CSAF documents in addition to two already existing methods. These don't allow the use of flexible queries as well as filtering, which makes it difficult for operators of software and hardware to use CSAF. An API is intended to simplify this process and thus advance the automation goal of CSAF.
First, it is evaluated whether the current standard allows the implementation of an API. Any conflicts are highlighted and suggestions for standard adaptations are made. Based on these results, the API is designed to meet the previously defined requirements. Subsequently, a proof of concept is successfully developed according to the design and extensively tested with specially prepared test data. Finally, the results and the necessary standard adjustments are summarized and justified.
The conceptual design and the implementation were successfully completed. However, during the implementation of the proof of concept, some routes could not be fully implemented.
Among the billions of smartphone users in the world, Android still holds more than 80% of the market share. The applications which the users install have a specific set of features that need access to some device functionalities and sensors that may hold sensitive information about the user. Therefore, Android releases have set permission standards to let the user know what information is being disclosed to the application. Along with other security and privacy improvements, significant changes to the permission scheme are introduced with the Android 6.0 version (API level 23). In this master thesis, the Android permission scheme is tested on two devices from different eras. The evolution of Android over the years is examined in terms of confidentiality. For each device, two applications are built; one focused on extracting every piece of information within the confidentiality scope with every permission declared and/or requested, and the other app focused on getting this type of information without user notification. The resulting analysis illustrates whether how and in what way the Android permission scheme declined or improved over time.
Threat Modeling is a vital approach to implementing ”Security by Design” because it enables the discovery of vulnerabilities and mitigation of threats during the early stage of the Software Development Life Cycle as opposed to later on when they will be more expensive to fix. This thesis makes a review of the current threat Modeling approaches, methods, and tools. It then creates a meta-model adaptation of a fictitious cloud-based shop application which is tested using STRIDE and PASTA to check for vulnerabilities, weaknesses, and impact risk. The Analysis is done using Microsoft Threat Modeling Tool and IriusRisk. Finally, an evaluation of the results is made to ascertain the effectiveness of the processes involved with highlights of the challenges in threat modeling and recommendations on how security developers can make improvements.
In the work at hand, we state that privacy and malleability of data are two aspects highly desired but not easy to associate. On the one hand, we are trying to shape data to make them usable and editable in an intelligible way, namely without losing their initial information. On the other hand, we are looking for effective privacy on data such that no external or non-authorized party could learn about their content. In such a way, we get overlapping requirements by pursuing different goals; it is trivial to be malleable without being secure, and vice versa. We propose four “real-world” use cases identified as scenarios where these two contradictory features are required and taking place in distinct environments. These considered backgrounds consist of firstly, cloud security auditing, then privacy of mobile network users and industry 4.0 and finally, privacy of COVID-19 tracing app users. After presenting useful background material, we propose to employ multiple approaches to design solutions to solve the use cases. We combine homomorphic encryption with searchable encryption and private information retrieval protocol to build an effective construction for the could auditing use case. As a second step, we develop an algorithm to generate the appropriate parameters to use the somewhat homomorphic encryption scheme by considering correctness, performance and security of the respective application. Finally, we propose an alternative use of Bloom filter data structure by adding an HMAC function to allow an outsourced third party to perform set relations in a private manner. By analyzing the overlapping bits occurring on Bloom filters while testing the inclusiveness or disjointness of the sets, we show how these functions maintain privacy and allow operations directly computed on the data structure. Then, we show how these constructions could be applied to the four selected use cases. Our obtained solutions have been implemented and we provide promising results that validate their efficiency and thus relevancy.
Das tiefe Lernen und die daraus entstehenden Technologien bieten eine neue Herausforderung für Unternehmen und privat Personen beiderlei. Deepfakes sind schon seit über vier Jahren im Internet verbreitet und in dieser Zeit wurden hauptsächlich politische Figuren Opfer der Technologie. Diese Arbeit nimmt sich das Ziel, die möglichen Attacken zu beschreiben und Gegenmaßnahmen dafür vorzustellen. Es wird zunächst Social Engineering erläutert und die technischen Grundlagen von Deepfakes gelegt. Daraufhin folgt ein Fallbeispiel, welches genauer aufzeigt, wie auch Unternehmen Opfer von Deepfake Attacken werden können. Diese Attacken fügen einen erheblichen finanziellen sowie Reputationsschaden an. Daher müssen verschiedene technische und organisatorische Maßnahmen gegenüber Deepfakes im Social Engineering Umfeld eingeführt werden. Durch die ständige Entwicklung der Technik werden diese Attacken in der Zukunft an Komplexität und Häufigkeit zunehmen. Unternehmen, Forscher und IT-Sicherheitsspezialisten müssen daher die Entwicklung dieser Attacken beobachten.
The identification of vulnerabilities is an important element of the software development process to ensure the security of software. Vulnerability identification based on the source code is a well studied field. To find vulnerabilities on the basis of a binary executable without the corresponding source code is more challenging. Recent research has shown how such detection can be performed statically and thus runtime efficiently by using deep learning methods for certain types of vulnerabilities.
This thesis aims to examine to what extent this identification can be applied sufficiently for a variety of vulnerabilities. Therefore, a supervised deep learning approach using recurrent neural networks for the application of vulnerability detection based on binary executables is used. For this purpose, a dataset with 50,651 samples of 23 different vulnerabilities in the form of a standardised LLVM Intermediate Representation was prepared. The vectorised features of a Word2Vec model were then used to train different variations of three basic architectures of recurrent neural networks (GRU, LSTM, SRNN). For this purpose, a binary classification was trained for the presence of an arbitrary vulnerability, and a multi-class model was trained for the identification of the exact vulnerability, which achieved an out-of-sample accuracy of 88% and 77%, respectively. Differences in the detection of different vulnerabilities were also observed, with non-vulnerable samples being detected with a particularly high precision of over 98%. Thus, the methodology presented allows an accurate detection of vulnerabilities, as well as a strong limitation of the analysis scope for further analysis steps.
With many advances in sensor technology and the Internet of Things, Vehicle Ad Hoc Net- work (VANET) is becoming a new generation. VANET’s current technical challenges are deploying decentralized architecture and protecting privacy. Because Blockchain features are decentralized, distributed, mass storage, and non-manipulation features, this paper designs a new decentralized architecture using Blockchain technology called Blockchain-based VANET. Blockchain-based VANET can effectively resolve centralized problems and mutual distrust between VANET units. To achieve this, it is needed to provide scalability on the blockchain to run for VANET. In this system, our focus is on the reliability of incoming messages on the network. Vehicles check the validity of the received messages using the proposed Bayesian formula for trust management system and some information saved in the Blockchain. Then, based on the validation result, the vehicle computes a rate for each message type and message source vehicle. Vehicles upload the computed rates to Roadside Units (RSUs) in order to calculate the net reliability value. Finally, RSUs using a sharding consensus mechanism generate blocks, including the net reliability value as a transaction. In this system, all RSUs collaboratively maintain the latest updated Blockchain. Our experimental results show that the proposed system is effective, scalable and dependable in data gathering, computing, organization, and retrieval of trust values in VANET.
In recent years, both the Internet of Things (IoT) and blockchain technologies have been highly influential and revolutionary. IoT enables companies to embrace Industry 4.0, the Fourth Industrial Revolution, which benefits from communication and connectivity to reduce cost and to increase productivity through sensor-based autonomy. These automated systems can be further refined with smart contracts that are executed within a blockchain, thereby increasing transparency through continuous and indisputable logging. Ideally, the level of security for these IoT devices shall be very high, as they are specifically designed for this autonomous and networked environment. This paper discusses a use case of a company with legacy devices that wants to benefit from the features and functionality of blockchain technology. In particular, the implications of retrofit solutions are analyzed. The use of the BISS:4.0 platform is proposed as the underlying infrastructure. BISS:4.0 is
intended to integrate the blockchain technologies into existing enterprise environments. Furthermore, a security analysis of IoT and blockchain present attacks and countermeasures are presented that are identified and applied to the mentioned use case.
In this work, an implementation of the somewhat homomorphic BV encryption scheme is presented. During the implementation, care was taken to ensure that the resulting program will be as efficient as possible i.e. fast and resource-saving. The basis for this is the work of Arndt Bieberstein, who implemented the BV scheme with respect to functionality. The presented implementation supports the basics of the BV scheme, namely (symmetric and asymmetric) encryption, decryption and evaluation of addition as well as multiplication. Additionally, it supports the encoding of positive and negative numbers, various gaussian sampling methods, basically infinitely large polynomial coefficients, the generation of suitable parameters for a use case, threading and relinearization to reduce the size of a ciphertext after multiplications. After presenting the techniques used in the implementation, it’s actual efficiency is determined by measuring the timings of the operations for various parameters.
In the field of network security, the detection of possible intrusions is an important task to prevent and analyse attacks. Machine learning has been adopted as a particular supporting technique over the last years. However, the majority of related published work uses post mortem log files and fails to address the required real-time capabilities of network data feature extraction and machine learning based analysis [1-5]. We introduce the network feature extractor library FEX, which is designed to allow real-time feature extraction of network data. This library incorporates 83 statistical features based on reassembled data flows. The introduced Cython implementation allows processing individual packets within 4.58 microseconds. Based on the features extracted by FEX, existing intrusion detection machine learning models were examined with respect to their real-time capabilities. An identified Decision-Tree Classifier model was thus further optimised by transpiling it into C Code. This reduced the prediction time of a single sample to 3.96 microseconds on average. Based on the feature extractor and the improved machine learning model an IDS system was implemented which supports a data throughput between 63.7 Mbit/s and 2.5 Gbit/s making it a suitable candidate for a real-time, machine-learning based IDS.
Die Nutzung Mobiler Endgeräte nimmt zu, Ortsgebundenheit immer mehr ab. Dieser Wandel bringt Veränderungen mit sich, so auch im Bereich Softwareinstallation. Das Installieren von Software über die Cloud ist im Konsumerbereich bereits stark vertreten. Nicht nur am Desktop, sondern insbesondere bei mobilen Endgeräte, wie Smartphones und Tablets wird Software, bzw. werden Apps fast ausschließlich nur noch über das Internet installiert.
Das ist ein aktuelles Thema für den Sensorhersteller SICK.
SICK entwickelt Sensoren, die programmierbar sind, sogenannte AppSpace-Sensoren, was über das Aufspielen von sogenannten SensorApps bereitgestellt wird.
Aufgrund dieser Entwicklung, dem Trend hin zu Cloudlösungen und Ortsungebundenheit, sieht das Unternehmen SICK die Notwendigkeit den Installationsprozess mithilfe einer mobilen App über das Internet anbieten zu können. Deshalb wurde im Rahmen der Arbeit eine hybride mobile App entwickelt, mit der es möglich ist, SensorApps über die Cloud auf ein SICK AppSpace-Gerät aufzuspielen. Dafür wurde auf Basis einer Nutzerrecherche ein Konzept entwickelt, welches im Anschluss mithilfe von gängigen Webtechnologien als hybride App umgesetzt wurde.
Möglichkeiten für die Verbesserung der Sicherheit von Endgeräten und Netzwerkstrukturen in der Cloud
(2021)
Meine Thesis soll sich mit dem Betrieb eines Unternehmens-Netzes mit Microsoft Tools mit und ohne Cloud beschäftigen. Dabei soll herausgearbeitet werden, in welchen Bereichen es Sinn ergibt, eine Cloudstrategie anzustreben und wo Unternehmen vielleicht empfohlen werden sollte, vorerst oder vielleicht auch langfristig bei der on-premise Variante zu bleiben.
Dafür werden Dinge wie rechtliche Aspekte, Datenschutz oder Kostenpunkte eher sekundär behandelt, da das Hauptaugenmerk auf der Sicherheit der Unternehmensdaten, Endgeräte und Server liegen soll.
Tatsächlich verfolgen bereits einige große Namen in Deutschland eine sogenannte "Cloud-first" Strategie, bei welcher versucht wird, alle möglichen Anwendungen in der Cloud unterzubringen. Auf Beweggründe und Motivation dieser Unternehmen wird kurz eingegangen.
Dann werden verschiedenste Bereiche behandelt, die im täglichen Unternehmensumfeld eine Rolle spielen, darunter fallen beispielsweise die Nutzung von Fileservern im Vergleich mit dem Cloud Ansatz OneDrive. Es soll die Frage beantwortet werden, ob eine vollständige Migration in die Cloud für verschiedene Bereiche Sinn ergibt, wie eben zum Beispiel den kompletten FileServer in die Cloud (im speziellen Fall OneDrive) umzuziehen.
Ein weiterer Unterpunkt ist die Nutzung eines Active Directorys bzw. von Domain Controllern in der Cloud über Azure AD. Hier wird insbesondere auch auf die Frage eingegangen, welche Unternehmen immer wieder beschäftigt, ob die, für die Konfiguration von Endgeräten sehr wichtigen, Group Policies in der Cloud erhalten bleiben bzw. ob und durch was sie ersetzt werden, oder ob und wie man sie migrieren kann.
Migration ist an dieser Stelle ein gutes Stichwort, denn ebenfalls soll aufgezeigt werden, wie herausfordernd die Migration verschiedenster on-premise Strukturen in die Cloud ist, und ob überhaupt bei allen Dingen eine Migration möglich ist. Interessant wird es hier möglicherweise bei legacy-Anwendungen.
Neben weiteren Themen wie dem sicherheitskritischen Allow-listing und verschiedenen Security-Ansätzen, denen mit einer Cloud-Strategie bessere Möglichkeiten gegeben werden kann, soll geklärt werden, welche Zusatzherausforderungen, aber auch Chancen die Cloud bieten kann und wird.
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Zusammengefasst soll am Ende klarer sein, für was sich die Microsoft Cloud Anwendungen momentan schon gut eignen, wo man abwägen muss, und in welchen Aspekten die Cloud sich zunächst noch weiterentwickeln muss, bevor sie sinnvoll und verlässlich nutzbar ist. Außerdem soll aufgeführt werden, in welchen Bereichen man in den nächsten Jahren, und vielleicht auch schon jetzt, kaum noch an der Cloud vorbeikommt, wenn man eine bestimmte Funktionalität, sei es nun eine Anwendung, die die Sicherheit des Unternehmens erhöht, oder eine die die Produktivität steigern soll, nutzen möchte.
Die Thesis soll also eine Möglichkeit für Unternehmen bieten, sich unabhängig über Cloudangebote, hier meist am Beispiel der Microsoft Cloud Services, zu informierten. Und außerdem einzuschätzen, wie komplex und realisierbar verschiedene Dinge sind.