Cyber Security exam 1
biometric verification
"is this person who she says she is?" -one-to-one matching: match against only the person's biometric in the database
biometric identification
"who is this person?", -one-to-many matching: match against all existing biometrics in the datbase
asymmetric cryptography
(aka public-key cryptography) -uses different keys to encrypt and decrypt messages
symmetric cryptography
(aka secret-key/private-key/shared-key cryptography) -uses the SAME key to encrypt and decrypt the plaintext -its simple and fast, but high risk if the key is leaked to an intruder
substitution methods: replace letters or letter groups
-Caesar cipher -ROT 13 -Multi-alphabet substitution -enigma
hashing
-a core element of a digital signature systems -a method of validating the integrity of content by detecting modification of the content
password management
-avoid writing passwords down -do not share with other people -change passwords regularly
security challenges of biometrics
-biometric spoofing: use artificial replications of biometric sample to trick system
Caesar Cipher
-developed in ancient Rome -named after Julius Caesar, who used it with a shift of three to protect important military messages -letters shift 3 back (D becomes A, E becomes B, etc)
physiological biometrics
-face print -facial thermogram -fingerprints -hand geometry -iris pattern -retinal pattern -vein pattern
behavioral biometrics
-gaits -keystroke dynamics -linguistic style -mouse dynamics -signature recognition -touch dynamics -voiceprint
types of system intrusions
-hackers -crackers: with malevolent intent
issues of risk assessment
-it is often difficult to calculate risk -indirect human factors are often ignored due to the difficulty of assessing them
password selection
-length -composition- use alphabetic, numeric, and punctuation characters -avoidance of reusing passwords from other systems -avoidance of dictionary words and personal information
Secure Hash Algorithm (SHA)
-most widely used
single-factor authentication
-only one factor is used to authenticate users -not recommended for critical systems
types of cryptography
-password hashing -encrypted emails -encrypted online payments -disk encryption -bitcoin
privacy challenges of biometrics
-personal data can be easily collected without consent -geolocation tracking technologies make constant surveillance easier -biometric identification stored in databased can be hacked
Rail fence (transposition)
-set the number of "rails" (key of the cipher) -write the plain text diagonally on successive "rails"
authentication factors: ownership factors
-something the user has (ID card, security token, implanted device, cell phone with built-in hardware token, etc)
Authentication factors: inherence factors
-something the user is or does (fingerprint, retinal pattern, signature, face, voice, keystroke dynamics, mouse dynamics, etc)
authentication factors: knowledge factors
-something the user knows (password, personal identification number, security question etc)
SSO (single sign-on
-use a single ID and password to access multiple systems -it reduces the number of passwords the user is required to remember
multi-factor authentication
-use multiple types of authentication factors
types of malware
-viruses -trojan horse -spyware -logic bomb -ransomware
three pillars of cybersecurity
1. people 2. process 3. technology
CIA triad (the three tenets of information security)
1. protect the CONFIDENTIALITY of data 2. preserve the INTEGRITY of data 3. promote the AVAILABILITY of data for authorized entity
popular algorithms in symmetric cryptography
Data encryption standard (DES), advanced encryption standard (AES), etc
types of insider threats - careless insiders
Ignore security rules or policies
Denial of Service (DoS) attacks
Make a system or network resource unavailable to its intended users by disrupting services of a host -distributed denial-of-service attacks are from multiple sources
What month is National Cyber Security Awareness Month?
October
popular algorithms of asymmetric cryptography
RSA, Diffie-Hellman, DSA, etc
symmetric vs asymmetric cryptography
Symmetric: -algorithms are faster -key must be transferred through external means Asymmetric: -algorithms are slower and more complex -RSA is not appropriate to encrypt long messages -more secure with two keys
define cybersecurity
The protection of computer systems and networks from the theft of or damage to their hardware, software, or electronic data, as well as from the disruption or misdirection of the services they provide.
what is Stuxnet
a malicious computer worm, reportedly used as attack weapon to damage Iran's uranium enrichment facility in 2007 and 2010
ROT 13
a special case of Caesar cipher -replace a letter with the 13th letter after it
types of insider threats - compromised insiders
accounts are compromised and exploited by cyber criminals
tokens
aka identity token, security token, access token -it is a physical device or software that is used to gain access to an electronically restricted resource
multi-alphabet substitution
an improvement on the Caesar cipher -use multiple numbers to shift letters ex: "lazy dog" becomes "mccz frh" --L => M, A =>C, Z=>C--
web attack
attacks intended to break web applications -SQL injection -cross site scripting
classic cryptograph
before computer age, cryptograph focused on message confidentiality
social engineering
breach through human nature
DAD triad from a hacker's view
disclosure, alteration, denial
insider threats
from people within the organization (employees, former employees, contractors or business associates) who have legitimate access
magic number seven (plus or minus two)
human's short-term memory has limited capacity -according to Miller, most adults can store 5 to 9 items in their short-term memory
human factors in cyber security
humans are the weakest link in security -technologies themselves do not guarantee a secure usage -we need to understand how users interact with technologies and use them effectively
third pillar of cybersecurity - technology
integrated tools for threat detection and mitigation
types of insider threats - malicious insiders
intentionally use their legitimate access to get data or intellectual property
the isolation fallacy
isolation does not make a computer system invulnerable to risk -an isolated computer system has very limited utility
why is Caesar cipher not secure?
it only has 26 possible keys (from 0 to 25) -can be easily hacked using "brute force" technique
human factors include:
lack of motivation -lack of awareness -risky belief -risky behavior -inadequate use of technology
entropy
measures the variation of uncertainty in bits
second pillar of cybersecurity - process
mechanisms to achieve cybersecurity strategies or goals
modern cryptography
much more secure than classic methods. -two main types: -symmetric and assymetric
first pillars of cybersecurity - people
people create risk, they are important asset and the first line of defense
organizational factors in cybersecurity
policies, culture, and management support -high workload and low staffing create a conflict of interest between functionality and information security
transposition method:
re-arrange the order of letters
risk assesment
risk assessment is a very common activity in cybersecurity lifecycle. -what are the vulnerabilities? -What is the likelihood that a vulnerability is exploited? -What is the impact?
creating usable security systems
security systems should be understandable, easy to locate, be visible, and be convenient
"penetrate and patch"
strategy used by security companies only addresses superficial, usually fleeting problems
what is wardriving
the act of searching for Wi-Fi wireless networks, usually from a moving vehicle using a laptop of smartphone
what is cryptography
the practice and study of techniques for secure communication in the presence of third parties called adversaries -it is the art to write or decipher secret code
keyspace
the range of possible values of a random key where c is the number of different values for each character; n is the length of the key
authorization
to verify that "you are permitted to do what you are trying to do"
authentication
to verify that "you are who you say you are"
a transposition cipher
unlike substitution methods, a transposition cipher does not replace letters, it changes the order of letters
digital signatures
used to verify the authenticity of messages, ensure integrity and non-repudiation -use asymmetric encryption in reverse order