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Kriminalitätsbekämpfung Im Dark Net: Neue Ermittlungsansätze Statt Verbote Schulze, Matthias

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Kriminalitätsbekämpfung Im Dark Net: Neue Ermittlungsansätze Statt Verbote Schulze, Matthias www.ssoar.info Kriminalitätsbekämpfung im Dark Net: neue Ermittlungsansätze statt Verbote Schulze, Matthias Veröffentlichungsversion / Published Version Arbeitspapier / working paper Zur Verfügung gestellt in Kooperation mit / provided in cooperation with: Stiftung Wissenschaft und Politik (SWP) Empfohlene Zitierung / Suggested Citation: Schulze, M. (2019). Kriminalitätsbekämpfung im Dark Net: neue Ermittlungsansätze statt Verbote. (SWP-Aktuell, 28/2019). Berlin: Stiftung Wissenschaft und Politik -SWP- Deutsches Institut für Internationale Politik und Sicherheit. https://doi.org/10.18449/2019A28 Nutzungsbedingungen: Terms of use: Dieser Text wird unter einer Deposit-Lizenz (Keine This document is made available under Deposit Licence (No Weiterverbreitung - keine Bearbeitung) zur Verfügung gestellt. Redistribution - no modifications). We grant a non-exclusive, non- Gewährt wird ein nicht exklusives, nicht übertragbares, transferable, individual and limited right to using this document. persönliches und beschränktes Recht auf Nutzung dieses This document is solely intended for your personal, non- Dokuments. Dieses Dokument ist ausschließlich für commercial use. All of the copies of this documents must retain den persönlichen, nicht-kommerziellen Gebrauch bestimmt. all copyright information and other information regarding legal Auf sämtlichen Kopien dieses Dokuments müssen alle protection. You are not allowed to alter this document in any Urheberrechtshinweise und sonstigen Hinweise auf gesetzlichen way, to copy it for public or commercial purposes, to exhibit the Schutz beibehalten werden. Sie dürfen dieses Dokument document in public, to perform, distribute or otherwise use the nicht in irgendeiner Weise abändern, noch dürfen Sie document in public. dieses Dokument für öffentliche oder kommerzielle Zwecke By using this particular document, you accept the above-stated vervielfältigen, öffentlich ausstellen, aufführen, vertreiben oder conditions of use. anderweitig nutzen. Mit der Verwendung dieses Dokuments erkennen Sie die Nutzungsbedingungen an. Diese Version ist zitierbar unter / This version is citable under: https://nbn-resolving.org/urn:nbn:de:0168-ssoar-62700-8 NR. 28 APRIL 2019 Einleitung Kriminalitätsbekämpfung im Dark Net Neue Ermittlungsansätze statt Verbote Matthias Schulze Gegenwärtig werden wieder Forderungen nach einem Verbot illegaler Bereiche im Internet – sogenannter Dark Nets – laut. Im Entwurf des Bundesinnenministeriums für das neue IT-Sicherheitsgesetz soll das »Zugänglichmachen von Leistungen zur Begehung von Straftaten« über internetbasierte Dienste unter Strafe gestellt werden. In der öffentlichen Wahrnehmung dominieren insbesondere die negativen Aspekte des Dark Nets: illegaler Waffen- und Drogenhandel, Cyber-Kriminalität und Kinder- pornografie. Neuere Daten zeigen jedoch, dass die Bedrohungen, die vom Dark Net ausgehen, weitaus geringer sind als häufig angenommen. Daher ist zu fragen, ob ein Verbot dieser Technologie sinnvoll, ohne negative Kollateraleffekte umsetzbar und zudem verhältnismäßig ist. Statt das Dark Net als solches verbieten zu wollen, sollte der Fokus darauf gerichtet werden, in neuen Ermittlungstechniken zu schulen und die internationale Kooperation bei der Strafverfolgung zu intensivieren. Dies wäre eine nachhaltige Lösung, da diese Fähigkeiten auch im Kampf gegen das weitaus grö- ßere Problem – Cyber-Kriminalität im regulären Internet – von Nutzen wären. Im politischen Diskurs ist oft nicht klar, auf der Protokoll- als auch auf der Anwen- was unter dem Dark Net verstanden wird. dungsebene. Das Internet ist ein Netzwerk, das Milliar- Zu den sichtbaren Bereichen zählt in erster den von Geräten mittels kleinerer Netzwer- Linie das World Wide Web. Das WWW in ke (LAN, WLAN, WAN, Mobilfunk) in eine Form von Websites ist lediglich der Bereich, große Infrastruktur integriert. Es werden der über den Browser sichtbar ist. Man drei Ebenen unterschieden: die Ebene der schätzt, dass es circa 1,6 Milliarden Web- Anwendungen des Internets (etwa das World sites im WWW gibt (davon wird die über- Wide Web bzw. WWW, Datenbanken oder wiegende Mehrheit nicht mehr aktualisiert). Apps), die Protokoll- bzw. Netzwerkebene der Unsichtbare Teile des Internets, das so- Datenübertragung und die Ebene der Hard- genannte Deep Net, sind zum Beispiel Daten- ware (Router, Glasfaserleitungen). Ein Merk- banken und Apps, die nicht öffentlich oder mal des Internets ist, dass es keinen zentra- nur eingeschränkt zugänglich sind. Dazu len Wachturm gibt, der das gesamte Netz- gehören Firmen- oder Regierungsnetzwerke. werk überblicken kann. Folglich gibt es Es wird vermutet, dass das gesamte Internet sichtbare und unsichtbare Bereiche, sowohl aus circa 40000 Deep Nets besteht. Das Deep Web wiederum wird häufig als dings kaum zu bekommen, weshalb hier jener Bereich des WWW bezeichnet, der mit Ungenauigkeiten gerechnet werden nicht von Suchmaschinen indiziert wird. muss. HS machen schätzungsweise zwischen Die Services von Facebook, Twitter und 3 und 6 Prozent des Datenverkehrs des Tor- Snapchat sind Teil des Deep Webs, da sie Netzwerks aus. Tor-Nutzer sind also nicht nur durch eine Applikation bzw. passwort- automatisch Dark-Web-Nutzer. geschützte Programminterfaces aufgerufen Die folgende Grafik veranschaulicht die werden können. Seiten, die nicht von Such- hierarchischen Beziehungen zwischen den maschinen erfasst werden, sind Teil des verschiedenen Teilnetzwerken: Deep Web. Das sind sozusagen Orte des WWW, die zwar existieren, aber auf keiner Karte auftauchen. Differenzierung von Netzwerk- und Zu guter Letzt gibt es noch verschiedene Web-Protokollen Dark Networks als Teilbereich des Internets. Anwendungs- Protokoll-Ebene Diese werden ebenfalls nicht von Such- ebene maschinen indiziert und basieren auf eige- Internet (TCP/IP) 40–50 Mrd. nen Übertragungsprotokollen (etwa dem Geräte in Onion Service Protocol). Dieses Protokoll 40000 Netz- verschlüsselt die Kommunikation und leitet werken sie mehrfach über sogenannte Relay-Server um, so dass Inhalte und IP-Adressen für World Wide HTTP ca. 1,6 Mrd. Außenstehende unsichtbar werden. Auch Web Websites innerhalb des Dark Nets gibt es wieder eine Deep Web Deep Net (802.11- Ebene der Netzwerkkommunikation, das WLAN, Ethernet) Tor Netzwerk (The Onion Routing), und eine Dark Web (Tor Dark Nets (z.B. ca.2Mio. Tor- Ebene der Anwendungen, in Form von Tor Hidden Services, Onion Service Nutzer; ca. Hidden Services (HS) oder anderen Anwendun- Freenet etc., Protocol, I2P und 110000 Hid- gen wie OnionShare (ein anonymer Cloud- Onion Sharing) weitere) den Services Speicher). Tor Hidden Services sind oft Websites, können aber auch Steuerungs- server zur Kontrolle von Bot-Netzen sein. Licht und Schatten Die Summe der Seiten bildet ein Dark Web. Viele der darin enthaltenen HS-Websites Weil Hidden Services bewusst verborgen können nur von denjenigen besucht wer- werden und fluktuieren, lassen sie sich den, die die Onion-Adresse des HS kennen. kaum wissenschaftlich auswerten. Auf- HS sind ein optionales Feature des Tor- grund solcher methodologischen Schwierig- Netzwerks, das es Website-Besuchern und keiten beschränken sich die meisten Unter- Website-Servern ermöglicht, sich anonym suchungen auf Ausschnitte des Dark Webs gegenüberzustehen. Technisch funktioniert zu bestimmten Zeitpunkten. Websites im dies wie ein sogenannter »toter Briefkasten«: Dark Web funktionieren mittlerweile so Website-Betreiber speisen eine Information wie ihre WWW-Pendants. Es gibt Shops, ein, die dann später von einem Website- Chats und Foren. Mangels effizienter Such- Besucher anonym aufgesammelt wird. maschinen dokumentieren zahlreiche Verglichen mit dem WWW machen HS- Wikis, welche Dark-Web-Websites welche Websites nur einen verschwindend gerin- Adresse haben. Aber auch über Google gen Anteil aller Websites aus. Es gibt circa lassen sich Adressen zu Dark-Web-Wikis 110000 HS. HS werden von nur 1–3 Pro- finden. Nutzerkommentare und Bewertun- zent der regelmäßig aktiven 2 Millionen gen sind üblich. Einer britischen, nicht- Tor-Nutzer überhaupt aufgerufen. Auf- wissenschaftlichen Studie zufolge sind circa grund der Anonymisierungsfunktion des 50 Prozent der Dienste im Dark Web als Tor-Netzwerks sind genaue Metriken aller- legal einzustufen. Darunter fallen etwa SWP-Aktuell 28 April 2019 2 Foren, in denen Themen diskutiert werden, pflichtigen Medikamenten eine häufige Pro- die in einigen Ländern tabuisiert sind. Auch duktkategorie auf Kryptomärkten. Die fol- Journalisten und Aktivisten nutzen das genden digitalen Güter waren 2018 auf Dark Net aus Angst vor Verfolgung durch einer Plattform namens Dream Market die autoritäre Regierungen. Sichere Kommuni- meistgehandelten: kompromittierte Nutzer- kationsplattformen für Whistleblower accounts (42%), Kreditkartendetails (29%), (»Secure Drops«) werden im Dark Web auch einfache Hacking-Tools (10%), Ausweis- von etablierten Organen wie der Washington dokumente (6,7%), komplexere Exploits Post gehostet. Tor wird insbesondere von (0,9%) und diverse Arten von Schadsoftware Bürgern in repressiven Regimen genutzt, (je ca. 0,7%). Zudem gibt es eine rege Com- um die Internet-Zensur zu umgehen und munity bösartiger Hacker, die sich dort auf westliche Dienste zugreifen zu können. zum Erfahrungsaustausch treffen. Aus diesem Grund sponsert das US State Auch der Vertrieb von Kinderpornografie Department seit 2011 die Entwicklung und findet über das Dark Web statt. Interessan- Verbreitung von Tor im Rahmen der Inter- terweise wird in diversen Kryptomärkten net Freedom Agenda. der Handel mit
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