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Summary Cyber Threats (Bsc Security Studies, Leiden University)
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A comprehensive summary of the course Cyber Threats that is taught in the second year of the bachelor Security Studies
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Leiden UniversityCyber Threats
Lecture 1: Introduction
In computer security, a threat is a possible danger that might exploit a vulnerability to breach security and therefore cause possible
harm. A threat can be either "intentional" or "accidental" or otherwise a circumstance, capability, action, or event. A cyber or
cybersecurity threat is a malicious act that seeks to damage data, steal data, or disrupt digital life in general. Cyber (in)security can be a
threat to individuals, groups/organisations, nations and the international community. Some examples of cyber threats include:
* Millennium Bug: coding error
* Cambridge Analytica: profiling
* Strava: publishing data
* OPCW: hack attempt
* Diginotar: trust issue
* Maastricht university: ransomware
* Grindr: selling data
* Stuxnet: sabotage — attack on physical property and people
* Schiphol: fuelling problem
* Banks: DDoS attacks
What is cyberspace?
“Cyberspace is composed of all the computerised networks in the world, as well as of all computerised end points, including
telecommunications networks, special purpose networks, the internet, computer systems, and computer-based systems. The concept
also includes the information stored, processed, and transmitted on the devices and between these networks.”
What is cybersecurity?
“Cyber security comprises technologies, processes and controls that are designed to protect systems, networks and data from cyber
attacks.” — “Effective cyber security reduces the risk of cyber attacks, and protects organisations and individuals from the
unauthorised exploitation of systems, networks and technologies.”
If it works, nothing happens. Is there a threat or are actors not interested? How can we tell? Focus on measurable outcomes. “A lot of
people still seem to think that you can solve the problem of cyber security with a couple of boxes, a bit of electronics and some clever
programming.”
But why do we care?
- Protection of critical national infrastructure (clean drinking water, electricity, internet, etc.)
- Privacy and sensitive data
- Financial reasons
Three-layer model:
- Outer layer — Governance
- In between — Socio-technical: people interacting with that technology
- Middle — Technical
Protection of data: CIA triad
- Confidentiality: information only available to authorised entities. Not only through hacking.
This could also be for instance wrong attachment in an email, data screens in public
displays, materials not removed correctly (e.g. secure bins), Grindr and Strava
- Integrity: can we trust the data, the whole data and noting but the data? No changes made
to data without detection. This includes changing data, adding data and deleting data. e.g.
millennium bug
- Availability: data available when needed. Systems up and running, people who should have
access have access and others not. e.g. Maastricht University ransomware attack
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Data backup: a copy of computer data taken and stored elsewhere so that it may be used to restore the original after a data loss
event. Primary data failures can be the result of hardware or software failure, data corruption, or a human-caused event, such as a
malicious attack (virus or malware), or accidental deletion of data. —> 3-2-1 (3 copies, 2 local, 1 in a galaxy far far away. e.g. DropBox,
TimeMachine, USB storage.
Multi-factor authentication: Multi-factor authentication is an authentication method in which a computer user is granted access only
after successfully presenting two or more pieces of evidence to an authentication mechanism: knowledge, possession, and inherence.
Something you know (e.g. password) have (e.g. a token, bank card) and are (e.g. fingerprint, iris, facial recognition).
- Upside: increased security
- Downside: often a bit more fuss
VPN: A virtual private network extends a private network across a public network, and enables users to send and receive data across
shared or public networks as if their computing devices were directly connected to the private network. It is a secure connection over
an insecure network. When would you want one? What might the dangers be? (e.g. your data can be sold).
Encryption is the process of encoding a message or information in such a way that only authorised parties can access it and those who
are not authorised cannot. Encryption itself does not prevent interference but denies the intelligible content to a would-be interceptor.
Not just messages, but files as well. Helps with the CIA triad. Also helps in starting a cyber attack(!).
End-to-end encryption: End-to-end encryption is a system of communication where only the communicating users can read the
messages. An example can be found within WhatsApp. But do we want it? Think about the issue with the FBI.
Public-key encryption: a cryptographic system that uses two pairs of keys: 1) public keys which may be disseminated widely, and 2)
private keys only for the owner. Share the public key, keep your private key secret! Used to encrypt/ decrypt messages.
Lecture 2: what is the Internet and how does it work?
The Advanced Research Projects Agency Network (ARPANET) was an early packet-switching network and the first network to
implement the TCP/IP protocol. It was created to make it easier for people to access computers and to have a more effective
communication method for the military as a response to Sputnik I (1957). Also for the protection of critical infrastructure. ARPA's goal
was to link different computers together, both to increase overall computer power and to decentralise information storage. As the
network development progressed, protocols for inter-networking were developed by which multiple separate networks could be joined
into a network of networks. ARPANET has three aspects:
1. Formulating technological problems and solutions
2. Sense of relevance of community of users
3. Open architecture of system, so that anyone can build on this
Architecture and rst steps
- Packet switching versus circuit switching (Leonard Kleinrock)
- Joseph Licklider envisioned a network in three ways:
1. Combination of hardware and software
2. Interaction between man and machine
3. Network of people (everyone can bring their expertise to the table)
- 1965: packet switching used for first message between two computers
‘Long’ distance connections: End of 60’s, most of the technology had been invented, but no centralisation — 1969: first link between
UCLA and SRI. They tried to send a message, this message came to be “LO” (they tried to say login, but the system crashed).
Mainstream use of Internet
- 1991: First webpage (CERN) — 1993: Mosaic, first popular browser, UN/US websites
- Cambridge develops webcam for critical process supervision as early as in 1991 (coffee machine)
- Hotmail starts in 1996, Google starts in 1998
Further developments and WWW:
- 1983: later on, they started implementing TCP/IP — 1984: public introduction of cyberspace
- 1989: Tim Berners-Lee proposed the World Wide Web
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Social media and mobile internet: 2004: Facebook, beginning of social media — 2006: Twitter — 2007: iPhone — 2008: First Android
So how does it work?
- Packets of information
- Transmitting packets via various routes
- TCP/IP model
Advantages and disadvantages:
Pros Cons
Faster services Privacy
Connectivity Accumulation of data
Availability of information Dark Web
TCP/IP model has different layers. They work together to send the message:
1) Link layer 2) Internet layer 3) Transport layer 4) Application layer
Encode information Router to router pathfinder: Speed Networked applications, e.g.
the packages goes through the World Wide Web
different cables
Local data transmission Best guess approach: which Delivery check Server/client communication
general direction are you
going — send a package into a
general direction and later on
look at the specifics
Order of data transmission: More specific as you move Window size Application protocol
what data is send first? along different hops
CSMA/CD: want to avoid that Infrastructure problems Matching limitations of
all computers talk at the same network + net-neutrality
time — it makes sure that
when you send a package the
other person is not using the
same line to send a package as
well (packages don’t collide)
Covering a single hop Trade-off: packages start small
and then you can send a
bigger one
e.g.: e.g.: e.g.: e.g.: HTTP, IMAP
Case study: Cambridge Analytica was a British political consulting firm which combined misappropriation of digital assets, data
mining, data brokerage, and data analysis with strategic communication during the electoral processes. The Facebook–Cambridge
Analytica data scandal was a major political scandal in early 2018 when it was revealed that Cambridge Analytica had harvested the
personal data of millions of people's Facebook profiles without their consent and used it for political advertising purposes.
- We made Brexit/ Trump happen
- Targeted advertising
- Facebook personality test
- Data of 50,000,000 users
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The case in short:
Facebook insisted that
Cambridge was not a
data breach, because it
routinely allows
researchers to have
access to user data for
academic purposes and
users consent to this. NB:
stealing someone’s data
is copying the data.
History
- David Stillwell & Michal Kosinski
- University of Cambridge Psychometrics Centre
- MyPersonality project
- Aleksandr Kogan based his work on Stillwel and Kosinski
- ThisIsYourDigitalLife-app
Personality
- Big five personality traits: OCEAN
1. Openness to new experiences
2. Conscientiousness
3. Extraversion
4. Agreeableness
5. Neuroticism
After data collection
- Machine learning
• Using computers to detect patterns in data
- For example weather predictions, possible risks or mapping spreading of
diseases
• Use these patterns to create algorithms
• Algorithms to make predictions on ‘new’ data
• Training and testing the algorithm
- Divide data in ‘training data’ and ‘test data’ to assess the quality of
algorithm
- Creating algorithms to predict
• Demographics, personality, interests, etc.
- More data collection and algorithm improvement/ extension
Consequences
- Anything you do online is tracked, collected and stored
- Just because you don’t actively share data, doesn’t mean your friends don’t either
- Algorithms allow for prediction of ‘hidden’ information
- Targeted advertising, but who knows?
- How much would you charge for your data?
- What about future technology that is applied to current data?
What happened to Cambridge Analytica?
- Public outcry over company’s action lead to the shut down in May 2018
- Emerdata ltd
- Data Propria (US 2020 elections) — but where is the data now?
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