TY - JOUR A1 - Oosthoek, Kris A1 - Dörr, Christian T1 - Cyber security threats to bitcoin exchanges BT - adversary exploitation and laundering techniques JF - IEEE transactions on network and service management : a publication of the IEEE N2 - Bitcoin is gaining traction as an alternative store of value. Its market capitalization transcends all other cryptocurrencies in the market. But its high monetary value also makes it an attractive target to cyber criminal actors. Hacking campaigns usually target an ecosystem's weakest points. In Bitcoin, the exchange platforms are one of them. Each exchange breach is a threat not only to direct victims, but to the credibility of Bitcoin's entire ecosystem. Based on an extensive analysis of 36 breaches of Bitcoin exchanges, we show the attack patterns used to exploit Bitcoin exchange platforms using an industry standard for reporting intelligence on cyber security breaches. Based on this we are able to provide an overview of the most common attack vectors, showing that all except three hacks were possible due to relatively lax security. We show that while the security regimen of Bitcoin exchanges is subpar compared to other financial service providers, the use of stolen credentials, which does not require any hacking, is decreasing. We also show that the amount of BTC taken during a breach is decreasing, as well as the exchanges that terminate after being breached. Furthermore we show that overall security posture has improved, but still has major flaws. To discover adversarial methods post-breach, we have analyzed two cases of BTC laundering. Through this analysis we provide insight into how exchange platforms with lax cyber security even further increase the intermediary risk introduced by them into the Bitcoin ecosystem. KW - Bitcoin KW - Computer crime KW - Cryptography KW - Ecosystems KW - Currencies KW - Industries KW - Vocabulary KW - cryptocurrency exchanges KW - cyber KW - security KW - cyber threat intelligence KW - attacks KW - vulnerabilities KW - forensics Y1 - 2021 U6 - https://doi.org/10.1109/TNSM.2020.3046145 SN - 1932-4537 VL - 18 IS - 2 SP - 1616 EP - 1628 PB - IEEE CY - New York ER - TY - JOUR A1 - Lambrecht, Jennifer A1 - Bogda, Katja A1 - Koch, Helvi A1 - Nottbusch, Guido A1 - Spörer, Nadine T1 - Längsschnittliche Effekte der häuslichen und institutionellen Lernumwelt auf den Wortschatz von Grundschulkindern – ein Vergleich T1 - Comparing the effect of home and institutional learning environment on children’s vocabulary in primary school JF - Journal for educational research online - JERO N2 - Es wird angenommen, dass für den frühen Kompetenzerwerb eines Kindes neben dem familiären Hintergrund und Merkmalen des Kindes die Lernumgebungen eine wichtige Rolle spielen. Die vorliegende Studie verfolgte das Ziel, die Effekte der häuslichen und der institutionellen Lernumgebung von Kindergartenkindern auf den frühen Wortschatzerwerb zu vergleichen und notwendige Bedingungen für einen kompensatorischen Effekt der institutionellen Lernumgebung zu überprüfen. Anhand längsschnittlicher Daten von N = 557 Kindergartenkindern aus dem deutschen Nationalen Bildungspanel (NEPS) wurde untersucht, in welchem Ausmaß der familiäre Hintergrund und die Merkmale eines Kindes die häusliche und institutionelle Lernumgebung prädizieren und in welchem Ausmaß diese wiederum den Wortschatz in der Vorschule und in der ersten Klasse vorhersagen. Um zu überprüfen, ob die beiden Lernumgebungen einen jeweils eigenständigen Beitrag zur Prädiktion des Wortschatzes leisten, wurden nahezu identische Indikatoren zur Operationalisierung verwendet. Mittels Strukturgleichungsmodellierung wurden die Effekte geschätzt. Die Studie zeigte, dass die häusliche und institutionelle Lernumgebung eines Kindes kleine sowie voneinander abgrenzbare Effekte auf den Wortschatz hatten. Dabei war die häusliche Lernumwelt stärker mit dem familiären Hintergrund assoziiert, während die institutionelle Lernumgebung stärker durch Merkmale des Kindes selbst prädiziert wurde. Dies eröffnet neue Möglichkeiten der Diskussion kompensatorischer Effekte. N2 - It is assumed that additionally to the family background and child characteris-tics, the children’s learning environments are crucial for the acquisition of early competencies. This study aimed to compare the eff ects of home and institutional learning environment on young children’s vocabulary and to test necessary con-ditions for a potential compensatory eff ect of the institutional learning environ-ment. Using longitudinal data from N = 557 preschool children (German National Educational Panel Study), we analysed to what extent family background and children’s characteristics predicted home and institutional learning environments and to what extent these learning environments predicted vocabulary in pre-school and primary school. In order to test if both learning environments pre-dict vocabulary separately, we used almost identical indicators to operationalize them. The effects were estimated within a structural equation model. The study revealed that both, home and institutional learning environment, had small and separate eff ects on children’s vocabulary. The home learning environment was more closely related to the family background, while the institutional learning en-vironment was more closely related to the children’s characteristics. This evokes new possibilities to discuss compensatory effect. KW - Home learning environment KW - Institutional learning environment KW - Vocabulary KW - Compensatory effect KW - Institutionelle Lernumgebung KW - Häusliche Lernumgebung KW - Wortschatz KW - Kompensatorischer Effekt Y1 - 2019 SN - 1866-6671 VL - 11 IS - 2 SP - 86 EP - 115 PB - Waxmann CY - Münster ER -