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The threat of data theft posed by self-propagating, remotely controlled bot malware is increasing. Cyber criminals are motivated to steal sensitive data, such as user names, passwords, account numbers, and credit card numbers, because these items can be parlayed into cash. For anonymity and economy of scale, bot networks have become the cyber criminal’s weapon of choice. In 2010 a single botnet included over one million compromised host computers, and one of the largest botnets in 2011 was specifically designed to harvest financial data from its victims. Unfortunately, current intrusion detection methods are unable to effectively detect data extraction techniques employed by bot malware. The research described in this Dissertation Report addresses that problem. This work builds on a foundation of research regarding artificial immune systems (AIS) and botnet activity detection. This work is the first to isolate and assess features derived from human computer interaction in the detection of data theft by bot malware and is the first to report on a novel use of the HTTP protocol by a contemporary variant of the Zeus bot.

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Die Arbeit besteht aus mehreren Studien zur Quantifizierung des Grundwasserstroms in Seen (Exfiltration; engl.: lacustrine groundwater discharge, LGD) und damit verbundener Nährstoffeinträge. In zwei einleitenden Kapiteln dieser Arbeit werden eine Gründe für die Vernachlässigung der Grundwasserexfiltration (LGD) in Seen und der daran gekoppelten Nährstoffeinträge identifiziert. Diese Literaturstudien fassen den aktuellen Kenntnisstand zum Einfluss des Grundwassers auf die Hydrologie von Seen und ihre Nährstoffhaushalte zusammen. Den Kern der vorliegenden Arbeit bilden zwei empirische Studien, die sich mit der Quantifizierung der grundwasserbürtigen Phosphor (P)-Fracht in den Arendsee in Deutschland befassen. Das Gesamtvolumen des Grundwasserzustroms wird basierend auf der Grundwasserneubildung im Einzugsgebiet des Sees ermittelt. Lokale Muster der Grundwasserexfiltration werden anhand von Temperaturtiefenprofilen des Seesediments bestimmt. Eine Kombination der Ergebnisse ermöglicht es, die quantitativen Daten mit lokalen Informationen zu unterstützen. Die Untersuchung der Grundwasserqualität zeigt, dass die P-Konzentrationen im Grundwasser im besiedelten Bereich teilweise stark erhöht sind. Als Konsequenz daraus haben die grundwasserbürtigen P-Frachten einen Anteil von mehr als 50% an der gesamten externen P-Last des Arendsees. Das Grundwasser ist damit eine maßgebliche Ursache für die Eutrophierung des Gewässers. Drei weitere Studien widmen sich der Entwicklung und Optimierung von Ansätzen zur qualitativen und quantitativen Bestimmung der Grundwasserexfiltration in Seen. Die kritische Auseinandersetzung mit den Ergebnissen der Studien zeigt die Notwendigkeit weiterer Forschung zur Verbesserung und Standardisierung der Methoden zur Bestimmung von LGD und damit verbundenen Stofftransporten auf. Der Fall des Arendsees sollte alle, Wissenschaftler und Praktiker, dazu motivieren, das Grundwasser als relevante Eutrophierungsquelle in Betracht zu ziehen. / The present work is a collection of studies on lacustrine groundwater discharge (LGD) and groundwater-borne phosphorus (P) loads. For a number of reasons, groundwater exfiltration (i.e., LGD) is often not considered in water and nutrient budgets of lakes. This is also and especially true for P which was often regarded to be immobile in groundwater until recently. Two chapters review the scientific literature regarding the impacts of groundwater on hydrology and nutrient budgets of lakes, respectively. They present mechanisms and processes of LGD as well as techniques and methods to measure LGD and related nutrient transports. Moreover, numbers of LGD volumes and loads reported in literature are presented. The core of the present work is represented by two case studies dealing with the quantification of P loads from LGD to a lake in Germany. A combination of different methods is applied to overcome the problem of quantitative large scale LGD determination without losing local spatial information. P concentrations in groundwater and LGD are investigated by detailed spatial water sampling. The results reveal that P is actually present in concentrations far above natural background concentrations in the urban groundwater. LGD-derived P loads account for more than 50% of the overall external P loads to the lake and by that contribute significantly to lake eutrophication. Three further studies are devoted to the development and improvement of approaches to determine LGD. Critical reviews of the above mentioned studies reveal the need for further research in order to standardize and improve methods for LGD and mass load determination. It is found that the appropriate method for LGD determination depends on the spatial scale of interest. The identification of P introduced by LGD as a main driver of lake eutrophication is an important finding which should encourage scientists, policy makers, and lake managers to consider groundwater as a relevant P source for lakes.

Cybersäkerhet är ett konstant växande hot mot organisationer, genom det ständigt ökade digitaliserade samhället, dock finns tecken på att medvetenheten hos organisationer ökar vad gäller cyberattacker och cybersäkerhet. Cyberattacker kan skapa konsekvenser som kan förhindra organisationens verksamhet. Detta lägger grunden till arbetet, att se hur försvarsförmågan har utvecklats. I värsta fall medför en cyberattack konsekvenser som kan äventyra en organisations överlevnadsförmåga. I och med det nya hotet ransomware, där hotaktören krypterar offrets filer och sedan kräver en lösensumma, har konsekvenserna kraftigt kommit att bli mer fatala. Metoderna för ransomware utvecklas av hotaktörerna vilket kan bidra till mer än bara ekonomiska konsekvenser för organisationen. Mot ransomware gäller i stort samma skyddsåtgärder som mot alla former av cyberattacker, däremot finns en del särskilt viktiga aspekter som belyses i detta arbete, till exempel implementering av backups, adekvat dataskydd samt god Patch Management (d.v.s. protokoll för att åtgärda sårbarheter i programvara). I arbetet sammanställs en branschkonsensus för hur organisationer skall arbeta gentemot cyberattacker, specifikt ransomwareattacker. Detta har gjorts genom en litteratur- och kvalitativ intervjustudie, som sedan har analyserats och diskuterats. Intervjustudien har genomförts hos organisationer som bedöms lämpliga för detta då de dagligen arbetar med cybersäkerhet. En av rekommendationerna är att ha en bra backuprutin, där man skapar, distribuerar och testar dessa. Genom arbetet belyses även hur god patch management bör implementeras. Slutligen presenteras även en ny metod, Ransomware 3.0 där hotaktörer stjäl en organisations IT-miljö för att sedan radera denna lokalt hos organisationen och sedan säljer tillbaka denna, som används av hotaktörerna, som hittills varit okänd, där vidare forskning bör vidtas. / Cybersecurity is a constantly growing threat against organisations due to the increasingly digitalisation of society, although there are signs that the consciousness at organisations has increased regarding cyberattacks and cybersecurity. Cyberattacks can create consequences that can restrain an organisations operations. This creates the foundation for this study, to see how the defence capabilities has developed. A cyberattack can, in the worst case scenario, threaten an organisations ability to survive. In regards to the new threat, ransomware, where the threat actor encrypts the victim’s files and demands a ransom, the consequences can be fatal. The new methods associated with ransomware, where the threat actor also exfiltrates the victim’s files, strongly impact the organisations ability to operate. This could lead to economic consequences, as well as damages towards stakeholder relations. Most protective measures applies towards ransomware, however there are some especially important aspects that are presented in this paper, such as implementation of backups, sufficient data protection as well as good Patch Management (protocol to patch vulnerabilities in software). In this paper, an industry consensus on how organisations should work against cyberattacks, especially ransomware, is compiled. This was performed through a litterature and a qualitative interview study. Both studies has been analysed and discussed.The interview study has been accomplished by interviewing appropriate organisations that work with cyber security daily. One of the recommendations is to have a good backup protocol, which implies creating, distributing and testing these backups. This paper also presents how a good patch management should be implemented. Finally, this paper presents a new method, Ransomware 3.0 where the threat actor steals an organisations IT environment, and then destroys the local copy at the organisation to then sell it back, that is used by the threat actors, that is still uncommon knowledge, where continued research have to be conducted.

The need to consider groundwater and surface water as a single resource has fostered the interest of the scientific community on the interactions between surface water and groundwater. The region below and alongside rivers where surface hydrology and subsurface hydrology concur is the hyporheic zone. This is the region where water exchange determines many biogeochemical and ecological processes of great impact on the functioning of rivers. However, the complex processes taking place in the hyporheic zone require a multidisciplinary approach. The combination of innovative point and distributed techniques originally developed in separated disciplines is of great advantage for the indirect identification of water exchange in the hyporheic zone. Distributed techniques using temperature as a tracer such as fiber-optic distributed temperature sensing can identify the different components of groundwater-surface water interactions based on their spatial and temporal thermal patterns at the sediment-water interface. In particular, groundwater, interflow discharge and local hyporheic exchange flows can be differentiated based on the distinct size, duration and sign of the temperature anomalies. The scale range and resolution of fiber-optic distributed temperature sensing are well complemented by geophysics providing subsurface structures with a similar resolution and scale. Thus, the use of fiber-optic distributed temperature sensing to trace flux patterns supported by the exploration of subsurface structures with geophysics enables spatial and temporal investigation of groundwater-surface water interactions with an unprecedented level of accuracy and resolution. In contrast to the aforementioned methods that can be used for pattern identification at the interface, other methods such as point techniques are required to quantify hyporheic exchange fluxes. In the present PhD thesis, point methods based on hydraulic gradients and thermal profiles are used to quantify hyporheic exchange flows. However, both methods are one-dimensional methods and assume that only vertical flow occurs while the reality is much more complex. The study evaluates the accuracy of the available methods and the factors that impact their reliability. The applied methods allow not only to quantify hyporheic exchange flows but they are also the basis for an interpretation of the sediment layering in the hyporheic zone. For upscaling of the previous results three-dimensional modelling of flow and heat transport in the hyporheic zone combines pattern identification and quantification of fluxes into a single framework. Modelling can evaluate the influence of factors governing groundwater-surface water interactions as well as assess the impact of multiple aspects of model design and calibration of high impact on the reliability of the simulations. But more importantly, this modelling approach enables accurate estimation of water exchange at any location of the domain with unparalleled resolution. Despite the challenges in 3D modelling of the hyporheic zone and in the integration of point and distributed data in models, the benefits should encourage the hyporheic community to adopt an integrative approach comprising from the measurement to the upscaling of hyporheic processes.