Domain 3 - Security Engineering Flashcards
(292 cards)
1
Q
Common Criteria ISO 15408
A
Structured methodology for documenting security requirements, documenting and validating
2
Q
What is a Protection Profile (PP)?
A
Set of security requirements for a category of products that meet specific consumer security needs
3
Q
What is the Target of Evaluation (TOE)?
A
The product
4
Q
What is the Security Target (ST)?
A
Identifies the security properties of TOE
5
Q
Security Functional Requirements (SFRs)
A
Specific individual security functions
6
Q
EAL0
A
Inadequate assurance
7
Q
EAL1
A
Functionally tested
8
Q
EAL2
A
Structurally tested
9
Q
EAL3
A
Methodically tested and checked
10
Q
EAL4
A
Methodically designed, tested and reviewed
11
Q
EAL5
A
Semi formally designed and tested
12
Q
EAL6
A
Semi formally verified design and tested
13
Q
EAL7
A
Formally verified design and tested
14
Q
NIST SP 800-27
A
Engineering Principles for IT Security
A Baseline for Achieving Security
15
Q
NIST SP 800-27 - Step 1
A
Initiation; need expressed, purpose documented, impact assessment
16
Q
NIST SP 800-27 - Step 2
A
Development/Acquisition; system designed, purchased, programmed, developed or constructed.
17
Q
NIST SP 800-27 - Step 3
A
Implementation; system tested and installed, certification and accreditation
18
Q
NIST SP 800-27 - Step 4
A
Operation/Maintenance; performs function, security operations, audits
19
Q
NIST SP 800-27 - Step 5
A
Disposal; disposition of information, HW and SW
20
Q
CMM (Maturity Model)
A
I Regularly Drink My OrangeJuice
Initial Repeatable Defined Managed Optimizing
21
Q
What are the functions of OS Kernel?
A
Loads & runs binary programs,
schedules task swapping, allocates memory &
tracks physical location of files on computers hard disk,
manages IO/OP requests from software, &
translates them into instructions for CPU
22
Q
Primary Storage
A
A temporary storage area for data entering and leaving the CPU
23
Q
Random Access Memory (RAM)
A
A temporary holding place for data used by the operating systems. It is volatile; meaning if it is turned off the data will be lost. Two types of RAM are dynamic and static.
24
Q
Dynamic Ram
A
Needs to be refreshed from time to time or the data will be lost.
25
Static RAM
Does not need to be refreshed
26
Read-Only Memory (ROM)
Non-volatile, which means when a computer is turned off the data is not lost;
for the most part ROM cannot be altered.
ROM is sometimes referred to as firmware
27
Erasable and Programmable Read-Only Memory (EPROM)
Nonvolatile like ROM, however EPROM can be altered.
28
Multitasking
Execute more than one task at the same time
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Multiprocessing
More than one CPU is involved
30
Multi-Threading
Execute different parts of a program simultaneously
31
Single state machine
Operates in the security environment at the highest level of classification of the information within the computer.
In other words, all users on that system must have clearance to access the info on that system.
32
Multi-state machine
Can offer several security levels without risk of compromising the system’s integrity.
33
CICS
Complex instructions. Many operations per instruction. Less number of fetches
34
RISC
Reduced instructions.
Simpler operations per instruction.
More fetches
35
1 GL
machine language (used directly by a computer)
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2GL
assembler
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3GL
FORTRAN. Basic pl/1 and C++
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4GL
Natural / focus and SQL
39
5GL
Prolog, lisp artificial intelligence languages based on logic
40
In regards to memory protection, describe Segmentation.
Dividing a computer’s memory into segments.
41
In regards to memory protection, what is Protection Keying?
Numerical values, Divides physical memory up into particular sized blocks, each of which has an associated numerical value called a protection key.
42
In regards to memory protection, what is Paging?
Divides memory address space into even size blocks called pages. To emulate that we have more RAM than we have.
SYSTEM KERNAL KNOWS THE LOCATION OF THE PAGE FILE
43
Data Execution Prevention
A system-level memory protection feature that is built into the OS DEP prevents code from being run from data pages such as the default heap, stacks, and memory pools
44
ITIL
The ITIL Core includes five publications addressing the overall life cycle of systems. ITIL as a whole identifies best practices that an organization can adopt to increase overall availability, and the Service Transition publication addresses configuration management and change management processes.
- Service Strategy
- Service Design
- Service Transition
- Service Operations
- Continuous Service Improvemen
45
What are the Types of Security Models?
State Machine Model
Information Flow Model
Noninterference Model
46
State Machine Model
describes a system that is always secure no matter what state it is in. If all aspects of a state meet the requirements of the security policy, that state is considered secure.
A transition occurs when accepting input or producing output.
A transition always results in a new state (also called a state transition).
A secure state machine model system always boots into a secure state, maintains a secure state across all transitions, and allows subjects to access resources only in a secure manner compliant with the security policy.
47
Information Flow Model
Focuses on the flow of information. Information flow models are based on a state machine model.
The Bell-LaPadula and Biba models are both information flow models. Information flow models don’t necessarily deal with only the direction of information flow; they can also address the type of flow.
Information flow models are designed to prevent unauthorized, insecure, or restricted information flow, often between different levels of security (these are often referred to as multilevel models).
The information flow model also addresses covert channels by specifically excluding all non-defined flow pathways.
48
Noninterference Model
Loosely based on the information flow model. However, instead of being concerned about the flow of information, the noninterference model is concerned with how the actions of a subject at a higher security level affect the system state or the actions of a subject at a lower security level.
Basically, the actions of subject A (high) should not affect the actions of subject B (low) or even be noticed by subject B.
The noninterference model can be imposed to provide a form of protection against damage caused by malicious programs such as Trojan horses.
49
What are some Techniques for Ensuring CIA?
Confinement
Bounds
Isolation
50
Confinement
To restrict the actions of a program. Simply put, process confinement allows a process to read from and write to only certain memory locations and resources. This is also known as sandboxing.
51
Bounds
A process consist of limits set on the memory addresses and resources it can access. The bounds state the area within which a process is confined or contained.
52
Isolation
When a process is confined through enforcing access bounds that process runs in isolation. Process isolation ensures that any behavior will affect only the memory and resources associated with the isolated process.
53
List 7 Security Models
```
MATRIX
BELL-LAPADULA
BIBA
CLARK WILSON
Information flow model
Brewer and Nash
Lipner Model – Confidentiality and Integrity, BLP + Biba 1st Commercial
```
54
MATRIX
- Provides access rights to subjects for objects
- Access rights are read, write and execute
- Columns are ACL’s
- Rows are capability lists - Supports discretionary access control
55
BELL-LAPADULA
MAC SUBJECTS/OBJECTS/CLEARANECS/
- Confidentiality model
- developed by DOD, thus classification
- Cannot read up (simple e=read security rule)
- Cannot write down (* property rule AKA CONFINEMENT PROPERTY). Exception is a trusted subject.
- Uses access matrix to specify discretionary access control
- Use need to know principle
- Strong star rule: read and write capabilities at the same level
- First mathematical model defined
- tranquility principle in Bell-LaPadula prevents security level of subjects from being changed once they are created
- Bell-LaPadula is concerned with preventing information flow from a high security level to a low security level.
56
BIBA
MAC “if I in it INTEGRITY MODEL”
- Integrity model
- Cannot read down (simple e=read integrity rule)
- Simple integrity property - cannot write up (* integrity)
- lattice based (least upper bound, greatest lower bound, flow policy)
- subject at one level of integrity cant invoke subject at a higher level of integrity
- Biba is concerned with preventing information flow from a low security level to a high security level.
- Focus on protecting objects from external threa
57
CLARK WILSON
- integrity model
- Cannot be tampered, logged, and consistency
- Enforces segregation of duty
- Requires auditing
- Commercial use
- Works with SCI Constrained Data items, data item whose integrity is to be preserved
- Access to objects only through programs
- An integrity verification procedure (IVP) is a procedure that scans data items and confirms their integrity.
58
Information flow model
- Each object is assigned a security class and value, and information is constrained to flow in the directions that are permitted by the security policy. Thus flow of information from one security level to another. (Bell & Biba)
59
Brewer and Nash
The Chinese Wall model provides a dynamic access control depending on user’s previous actions. This model prevents conflict of interests from members of the same organization to look at information that creates a conflict of another member of that organization.
60
Lipner Model
Confidentiality and Integrity, BLP + Biba 1st Commercial Model
61
Graham-Denning
A computer security model that shows how subjects and objects should be securely created and deleted.
The model is based on the Access Control Matrix model
62
TAKE-GRANT
uses a direct graph to specify the rights that subjects can transfer to objects or that subjects can take from other subjects
- Uses STATES and STATE TRANSTIONS
63
Describe Composition Theories?
Some other models that fall into the information flow category build on the notion of how inputs and outputs between multiple systems relate to one another— which follows how information flows between systems rather than within an individual system.
These are called composition theories because they explain how outputs from one system relate to inputs to another system.
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Cascading
Input for one system comes from the output of another system.
65
Feedback
One system provides input to another system, which reciprocates by reversing those roles (so that system A first provides input for system B and then system B provides input to system A)
66
Hookup
One system sends input to another system but also sends input to external entities
67
MAC
Mandatory Access Control
Subjects are labelled as to their level of clearance. Objects are labelled as to their level of classification or sensitivity.
68
User
perform work task
69
Data Owners
protect data
70
Data Custodians
classify and protect data
71
Information Technology Security Evaluation Criteria (ITSEC)
A structured set of criteria for evaluating computer security within products and systems.
Used in Europe Only
Addresses CIA
- refers to any system being evaluated as a target of evaluation
(TOE).
- does not rely on the notion of a TCB, and it doesn’t require that a system’s security components be isolated within a TCB.
- includes coverage for maintaining targets of evaluation after changes occur without requiring a new formal evaluation.
Certification
72
TOE
Target of Evaluation refers to any system being evaluated
73
Certification
Evaluation of security features and safeguards if it meets requirements.
Certification is the comprehensive evaluation of the technical and nontechnical security features of an IT system and other safeguards made in support of the accreditation process to establish the extent to which a particular design and implementation meets a set of specified security requirements
74
Accreditation
The formal declaration by the designated approving authority (DAA) that an IT system is approved to operate in a particular security mode using a prescribed set of safeguards at an acceptable level of risk.
Once accreditation is performed, management can formally accept the adequacy of the overall security performance of an evaluated system.
75
System accreditation
A major application or general support system is evaluated
76
Site accreditation
The applications and systems at a specific, self-contained location are evaluated
77
Type accreditation
An application or system that is distributed to a number of different locations is evaluated
78
Trusted Computer System Evaluation Criteria TCSEC: (Orange book)
From the U.S. DoD, it evaluates operating systems, application and systems.
It doesn’t touch the network part. It only addresses confidentiality!
79
ITSEC: 1
TCSEC: D
Minimal protection, any systems that fails higher levels
80
ITSEC: 2
TCSEC: C1
DAC; (identification, authentication, resource protection).
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ITSEC: 3
TCSEC: C2
DAC; Controlled access protection (object reuse, protect audit trail).
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ITSEC: 4
TCSEC: B1
MAC; (security labels) based on Bell LaPadula security model. Labeled security (process isolation, devices
83
ITSEC: 5
TCSEC: B2
MAC; Structured protection (trusted path, covert channel analysis). Separate operator/admin roles. Configuration management
84
ITSEC: 6
TCSEC: B3
MAC; security domain (trusted recovery, Monitor event and notification).
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ITSEC: 7
TCSEC: A
MAC; Formal, verified protection
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What are the Operational assurance requirements for TCSEC?
- System Architecture
- System Integrity
- Covert Channel analysis - Trusted Facility Management
- Trusted recovery
87
Rainbow series: Red
trusted network
88
Rainbow series: Orange
TCSEC evaluation
89
Rainbow series: Brown
Trusted facilities management
90
Rainbow series: Green
Password management
91
ISO 27001
Focus on the standardization and certification of an organization’s information security management system (ISMS), security governance, a standard; ISMS.
Info security minimum systems
92
ISO 27002
(inspired from ISO 17799) – a guideline which lists security control objectives and recommends a range of specific security controls;
more granular than 27001. 14 areas
BOTH INSPIRED FROM BS7799
93
Control Frameworks
Consider the overall control framework or structure of the security solution desired by the organization
94
COBIT
Control Objectives for Information and Related Technology, is a documented set of best IT security practices crafted by the Information Systems Audit and Control Association (ISACA).
It prescribes goals and requirements for security controls and encourages the mapping of IT security ideals to business objectives.
95
COBIT 5
Based on five key principles for governance and management of enterprise IT:
Principle 1: Meeting Stakeholder Needs
Principle 2: Covering the Enterprise End-to-End
Principle 3: Applying a Single, Integrated Framework
Principle 4: Enabling a Holistic Approach
Principle 5: Separating Governance from Management.
COBIT is used not only to plan the IT security of an organization but also as a guideline for auditors.
96
What is Virtualization?
Used to host one or more operating systems within the memory of a single host computer.
Such an OS is also known as a guest operating system. From the perspective that there is an original or host OS installed directly on the computer hardware, the additional Oses hosted by the hypervisor system are guests.
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Virtual machine
Simulated environment created by the OS to provide a safe and efficient place for programs to execute
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Virtual SAN
Software-defined shared storage system is a virtual re-creation of a SAN on top of a virtualized network or an SDN.
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TOC/TOU attack
Race condition exploits, and communication disconnects are known as state attacks because they attack timing, data flow control, and transition between one system state to another.
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RACE
Two or more processes require access to the same resource and must complete their tasks in the proper order for normal functions
101
Register
CPU also includes a limited amount of onboard memory, known as registers that provide it with directly acessible memory locations that the brain of the CPU, the arithmetic-logical unit (ALU), uses when performing calculations or processing instructions, small memory locations directly in the CPU.
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Stack Memory Segment
Used by processors to communicate instructions and data to each other
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Monolithic Operating System Architecture
All of the code working in kernel mode/system mode in an ad hoc and nonmodularized OS
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Memory Addressing
When using memory resources, the processor must have some means of referring to various locations in memory. The solution to this problem is known as addressing.
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Register Addressing
When the CPU needs information from one of its registers to complete an operation, it uses a register address (for example, “register 1”) to access its contents.
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Immediate Addressing
Is not a memory addressing scheme per se but rather a way of referring to data that is supplied to the CPU as part of an instruction. For example, the CPU might process the command “Add 2 to the value in register 1.” This command uses two addressing schemes. The first is immediate addressing— the CPU is being told to add the value 2 and does not need to retrieve that value from a memory location— it’s supplied as part of the command. The second is register addressing; it’s instructed to retrieve the value from register 1.
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Direct Addressing
In direct addressing, the CPU is provided with an actual address of the memory location to access. The address must be located on the same memory page as the instruction being executed. Direct addressing is more flexible than immediate addressing since the contents of the memory location can be changed more readily than reprogramming the immediate addressing’s hard-coded data. Indirect Addressing
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Indirect addressing
uses a scheme similar to direct addressing. However, the memory address supplied to the CPU as part of the instruction doesn’t contain the actual value that the CPU is to use as an operand. Instead, the memory address contains another memory address (perhaps located on a different page). The CPU reads the indirect address to learn the address where the desired data resides and then retrieves the actual operand from that address.
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Base + Offset Addressing
uses a value stored in one of the CPU’s registers as the base location from which to begin counting. The CPU then adds the offset supplied with the instruction to that base address and retrieves the operand from that computed memory location.
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PaaS
Platform-as-a-Service is the concept of providing a computing platform and software solution stack as a virtual or cloudbased service.
Essentially, this type of cloud solution provides all the aspects of a platform (that is, the operating system and complete solution package).
The primary attraction of PaaS is the avoidance of having to purchase and maintain high-end hardware and software locally.
Customer supplies application code that the vendor then executes on its own infrastructure
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SaaS
Software-as-a-Service, is a derivative of PaaS. SaaS provides on-demand online access to specific software applications or suites without the need for local installation. In many cases, there are few local hardware and OS limitations.
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IaaS
Infrastructure-as-a-Service, takes the PaaS model yet another step forward and provides not just on-demand operating solutions but complete outsourcing options.
This can include utility or metered computing services, administrative task automation, dynamic scaling, virtualization services, policy implementation and management services, and managed/ filtered Internet connectivity.
Deployment Models, parent organization still responsible for patching OS of virtual hosts,
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CaaS
not a TERM!
- Private; cloud-based assets for a single organization. Organizations can create and host private clouds using their own resources.
- Community; provides cloud-based assets to two or more organizations. Maintenance responsibilities are shared based on who is hosting the assets and the service models.
- Public; model includes assets available for any consumers to rent or lease and is hosted by an external CSP. Service level agreements can be effective at ensuring the CSP provides the cloud-based services at a level acceptable to the organization.
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What methods can provide Database Security?
Aggregation
| Inference
115
Aggregation
SQL provides a number of functions that combine records from one or more tables to produce potentially useful information.
Aggregation is not without its security vulnerabilities.
Aggregation attacks are used to collect numerous low-level security items and combine them to create something of a higher security level or value.
116
Inference
Involve combining several pieces of non-sensitive information to gain access to information that should be classified at a higher level. However, inference makes use of the human mind’s deductive capacity rather than the raw mathematical ability of modern database platforms.
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Data Warehousing
Large databases, store large amounts of information from a variety of databases for use with specialized analysis techniques.
118
Data Mining
Technique allow analysts to comb through data warehouses and look for potential correlated information.
119
Data dictionary
Commonly used for storing critical information about data, including usage, type, sources, DBMS software reads the data
ISO
120
What is the purpose of Encryption?
Protect transmitted information from being read and understood except by the intended recipient
121
Substitution
like shifting and rotating alphabets, can be broken by statistical looking at repeating characters or repeats
122
Vernam
cipher (one time pad): - key of a random set of non- repeating characters
123
Information Theory
Claude Elmwood Shannon
124
Transposition
Permutation is used, meaning that letters are scrambled.
The key determines positions that the characters are moved to, for example vertical instead of horizontal
125
Null Cipher
used in cases where the use of encryption is not necessary but yet the fact that no encryption is needed must be configured in order for the system to work. Ex. Testing, stenograph
126
Key Length
use with each algorithm based on the sensitivity of information transmitted, longer key the better!
127
Key space
is the range of values that are valid for use as a key for a specific algorithm. A key space is defined by its bit size. Bit size is nothing more than the number of binary bits (0s and 1s) in the key.
The key space is the range between the key that has all 0s and the key that has all 1s.
Key space doubles each time you add a bit to key length, which makes cryptanalysis more difficult.
128
Key Clustering
when different encryption keys generate the same ciphertext from the same plaintext message BAD
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Synchronous
each encryption or decryption request is performed immediately
130
Asynchronous
encrypt/decrypt request are processed in queues.
131
Hash Function
one-way mathematical operation that reduces a message or data file into a smaller fixed length output. Encrypted using private key of sender.
132
Registration Authority
– performs certificate registration services on behalf of a CA. RA verifies user credentials
133
Certificate Authority
PKI, entity trusted by one or more users as an authority in a network that issues, revokes, and manages digital certificates
134
Key Space
represents the total number of possible values of keys in a cryptographic algorithm for the encryption of a plaintext block sequence to increase security by introducing additional cryptographic variance. HOW HARD TO BRUTE FORCE
135
Transposition/permutation
process of reordering plaintext to hide the message rambo = ombar
136
SP-network
process described by Claude Shannon used in most block ciphers to increase their strength
137
Confusion
mixing the key values during repeated rounds of encryption, make the relationship between ciphertext and key as complex as possible
138
Diffusion
mix location of plaintext throughout ciphertext, change of a single bit should drastically change hash, dissipate pattern
139
Meet in the Middle
Attackers might use a meet-in-the-middle attack to defeat encryption algorithms that use two rounds of encryption.
This attack is the reason that Double DES (2DES) was quickly discarded as a viable enhancement to the DES encryption (it was replaced by Triple DES (3DES, TDES, EEE, EDE).
Key
140
Block Cipher
segregating plaintext into blocks and applying identical encryption algorithm and key
141
Cipher
cryptographically transformation that operates on characters or bits. DES, word scramble, shift letters
142
Cipher text or Cryptogram
unintelligible message, encrypt text Clustering – situation wherein plain text messages generates identical cipher text messages using the same algorithm but with different crypto-variables or keys
143
Codes
cryptographic transformation that operates at the level of words or phrases, one by land, two by sea
144
Cryptanalysis
breaking the cipher text,
145
Cryptographic Algorithm
Step by step procedure to encipher plaintext and decipher cipher text
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Cryptography
the art and science of hiding the meaning of communications from unintended recipients. (Greek: kryptos=hidden, graphein=to write)
147
Cryptology
cryptography + cryptanalysis
148
Cryptosystem
set of transformations from a message space to cipher space
149
Decipher
To make the message readable, undo encipherment process
150
Encipher
make message unintelligible
151
End-to-end encryption
Encrypted information that is sent from point of origin to destination. In symmetric encryption this means both having the same identical key for the session
152
Exclusive OR
Boolean operation that performs binary addition
153
Key or Crypto variable
Information or sequence that controls the enciphering and deciphering of messages
154
Link encryption
stacked encryption using different keys to encrypt each time
155
One Time Pad
encipher each character with its own unique key that is used only once, unbreakable supposedly
156
PGP (GPG)
encrypt attached files
157
Plaintext
message in clear text readable form
158
Steganography
secret communications where the existence of a message is hidden (inside images for example)
159
Dumpster Diving
of going through someone’s trash to find useful or confidential info –it is legal but unethical in nature
160
Phishing
act of sending spoofed messages that pretend to originate from a source the user trusts (like a bank)
161
Social Engineering
act of tricking someone into giving sensitive or confidential info that may be used against the company
162
Script kiddie
someone with moderate hacking skills, gets code from the Internet.
163
Red boxing
pay phones cracking
164
Black Boxing
manipulates toll-free line voltage to phone for free
165
Blue Boxing
tone simulation that mimics telephone co. system and allows long distance call authorization
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White box
dual tone, multifrequency generator to control phone system
167
Phreakers
– hackers who commit crimes against phone companies
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Salami
removal of a small amount of money otherwise known as skimming
169
Zero-knowledge proof
a communication concept. A specific type of information is exchanged but no real data is transferred, as with digital signatures and digital certificates. Understand split knowledge. “magic door”
170
Split knowledge
means that the information or privilege required to perform an operation is divided among multiple users.
This ensures that no single person has sufficient privileges to compromise the security of the environment.
M of N Control (multiparty key recovery) is an example of split knowledge.
171
Skipjack
Like many block ciphers, Skipjack operates on 64-bit blocks of text.
It uses an 80-bit key and supports the same four modes of operation supported by DES.
Skipjack was quickly embraced by the US government and provides the cryptographic routines supporting the Clipper and Capstone encryption chips.
However, Skipjack has an added twist— it supports the escrow of encryption keys.
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What are the Goals of Cryptography?
```
Confidentiality
Integrity
Proof of origin
Non-repudiation
Protect data at rest Protect data in transit
```
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Key Clustering
when different encryption keys generate the same ciphertext from the same plaintext message
174
Work Factor
time and effort required to break a protective measure
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Kirchhoff’s Principle
all but key, secure Synchronous and self-synchronous
Random Number Generators (RNGs) Vigenere Cipher – uses key words and numerous rows (traditionally 26), each one of which is offset by one.
176
Security Monitoring
- Reference Monitor and security kernel are used to determine whether a user should be allowed to access an object
- “complete mediation” means that all subjects must be authenticated and their access rights verified before they can access any object
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Stream-based Ciphers
Operate on one character or bit of a message (or data stream) at a time.
The Caesar cipher is an example of a stream and shift cipher.
The one-time pad is also a stream cipher because the algorithm operates on each letter of the plaintext message independently.
SUBSTITUTION, real-time Advantage – bit by bit substitution with XOR & keystream Emulates one time pad
No size difference between plaintext and ciphertext
Disadvantage Can be difficult to implement correctly
Generally weaker than block mode cipher
Difficult to generate a truly random unbiased keystream
Wireless
Stream Cipher Uses WEP, WPA – use WEP if you have nothing else
RC4
Audio Visual
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Block-based Ciphers
Ciphers operate on “chunks,” or blocks, of a message and apply the encryption algorithm to an entire message block at the same time.
The transposition ciphers are examples of block ciphers. SUBSTITUTION & TRANSPOSITION
No longer common/effective attack on wireless networks
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CBC Cipher Block Chaining
blocks of 64 bits with - 64bits initialization vector. Errors will propagate
180
ECB Electronic Code Book
right block/left block pairing 1-1. Replication occurs. Secure short messages
181
Cipher Feedback CFB
stream cipher where the cipher text is used as feedback into key generation. errors will propagate
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Output Feedback OFB
stream cipher that generates the key but XOR-ing the plaintext with a key stream. No errors will propagate
183
Counter (CTR)
secure long messages
184
Symmetric Cryptography
Both the receiver and the sender share a common secret key.
- Larger key size is safer > 128
- Can be time-stamped (to counter replay attacks)
- Does not provide mechanisms for authentication
- non-repudiation
185
Examples of Symmetric Cryptography
DEA Data Encryption Algorithm
AES Advanced Encryption Standard
Rijndael Block Cipher Algorithm
RC5
IDEA - International Data Encryption Algorithm
Two fish
Blowfish
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DES (data Encryption Standard)
- DEA Data Encryption Algorithm x3.92, using 64 block size and 56bit key with 8bits parity
- 16-rounds of substitution and transposition cryptosystem
- Adds confusion(conceals statistical connect between cipher text and plaintext) and Diffusion (spread the influence of plaintext characters over many cipher text characters by means of transposition like HIDE IHED)
- Triple des = three times encrypted DES, preferably with 3 different keys = DES-EE3. Actual key length = 168 bits.
Uses 48 rounds of computations (3x16) -
Replaced by AES Advanced Encryption Standard
187
AES Advanced Encryption Standard
- one of the most popular symmetric encryption algorithms
- NIST selected it as a standard replacement for the older Data Encryption Standard (DES) in 2001.
- BitLocker (a full disk encryption application used with a Trusted Platform Module) uses AES
- Microsoft Encrypting File System (EFS) uses AES for file and folder encryption
- AES supports key sizes of 128 bits, 192 bits, and 256 bits, and the US government has approved its use to protect classified data up to top secret
- Larger key sizes add additional security, making it more difficult for unauthorized personnel to decrypt the data.
- Keys are 128, 192, and 256 bits, blocks 128 bits.
188
Rijndael Block Cipher Algorithm
for speed, simplicity and resistance against known attacks. Variable block length and variable key lengths (128,192 and 256 bits)
189
RC5
variable algorithm up 0 to 2048 bits key size
- Rivest Cipher 5, or RC5, is a symmetric algorithm patented by Rivest, Shamir, and Adleman (RSA) Data Security, the people who developed the RSA asymmetric algorithm.
RC5 is a block cipher of variable block sizes (32, 64, or 128 bits) that uses key sizes between 0 (zero) length and 2,040 bits.
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IDEA
International Data Encryption Algorithm 64 bit plaintext and 128 key length with confusion and diffusion used in PGP software patented requires licenses fees/free noncom.
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Two fish
key lengths 256 bits blocks of 128 in 16rounds
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Blowfish
by Bruce Schneider key lengths 32 to 448 bits, used on Linux systems that use bcrypt (DES alternative)
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Asymmetric Cryptography
Sender and receiver have public and private keys.
Public to encrypt a message, private to decrypt
Slower than symmetric, secret key (100 to 1000)
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Examples of Public Key Algorithms (Asymmetric)
```
RSA
Diffie Hellman Key exchange
el Gamal
DSA Digital Signature Algorithm
ECC - Elliptic Curve Cryptosystem
```
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RSA
(Rivest, Shamir, & Adleman) works with one way math with large prime numbers (aka trap door functions).
Can be used for encryption, key exchange and digital signatures)
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Diffie Hellman Key exchange
About exchanging secret keys over an insecure medium without exposing the keys
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el Gamal
works with discrete logarithms, based on Diffie Hellman
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DSA Digital Signature Algorithm
the US Government Equivalent of the RSA algorithm
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ECC - Elliptic Curve Cryptosystem
mathematical properties of elliptical curves, IT REQUIRES FEWER RESOURCES THAN RSA.
Used in low power systems (mobile phones etc.)
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Hybrid Cryptography
Uses both asymmetrical and symmetrical encryption
- asymmetrical for key exchange
- symmetrical for the bulk - thus it is fast
- example: SSL, PGP, IPSEC S/MIME
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Message Digest
summaries of a message’s content (not unlike a file checksum) produced by a hashing algorithm, checksum?
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MAC
Message Authentication Code
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Security Assertion Markup Language (SAML)
SAML is an XML-based convention for the organization and exchange of communication authentication and authorization details between security domains, often over web protocols.
SAML is often used to provide a web-based SSO (single sign-on) solution.
If an attacker can falsify SAML communications or steal a visitor’s access token, they may be able to bypass authentication and gain access SAML is a common protocol used for SSO on the Internet.
*Best choice to support a federated identity management system,
Does not have a security mode and relies on TLS and digital signatures
If home organization offline implement a cloud based system
User training about SSO directs a good idea
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Service Provisioning Markup Language (SPML)
Allow platforms to generate and respond to provisioning requests
It is a newer framework based on XML but specifically designed for exchanging user information for federated identity single sign-on purposes.
It is based on the Directory Service Markup Language (DSML), which can display LDAP-based directory service information in an XML format.
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Cyber-Physical Systems
Smart networked systems with embedded sensors, processors, and actuators that are designed to sense and interact with the physical world
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Scythe
wound papyrus around a wooden rod to see message
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Substitution character
shifting 3 character (C3) for example in the one (mono-alphabet) alphabet system
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Cipher disks
2 rotating disks with an alphabet around it
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Jefferson disks
26 disks that cipher text using an alignment bar
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Unix
uses rot 13 rotate 13 places in the alphabet
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Hagelin machine (M-209)
mechanical cryptographic machine
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Enigma
poly-alphabetic substitution cipher machine
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SABSA
Sherwood Applied business security architecture chain of traceability, 6 layer
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TOGAF
method step by step process and framework. These are the tools to go forward FRAMEWORK AND METHOD
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Zachman Framework
common context to understand a complex architecture, communication and collaboration
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Asymmetric Alogorithms
- Uses a pair of keys (private and public) for encryption and decryption
- Built upon hard to resolve mathematical problem using factorization, discreet logarithms, and the elliptic curve theory.
- Slower than symmetric alogorithm
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Types of Asymmetric Systems
```
Diffie-Helman
RSA
El Gamal
Elliptic Curve Cryptosystems
LUC
Knapsack
Zero Knowledge Proof
```
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Types of Symmetric Algorithms
```
DES
3DES
AES
IDEA
Blowfish
Twofish
RC4
RC5
RC6
CAST
SAFER
Serpent
```
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Symmetric vs. Asymmetric Key Systems
Symmetric
- Same, shared keys
- Key Exchange is Out-of-band
- Speed is Faster
- Used for Bulk encryption such as files and communication
- Security service provided is Confidentiality
Asymmetric
- Public and Private Keys
- Key exchange: In Bound. Symmetric key is encrypted and sent with message
- Slower and more complex
- Use is Key encryption and key distribution
- Security service provided is Confidentiality, Authentication, Non-Repudiation
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Public Key Infrastructure (PKI).
In the public key infrastructure, certificate authorities (CAs) generate digital certificates containing the public keys of system users.
Users then distribute these certificates to people with whom they want to communicate.
Certificate recipients verify a certificate using the CA’s public key. X.509 standard = PKI .
Serial number, owner, issuer name Integrity (hash code and message digest), access control, confidentiality (by encryption), authentication (digital certificates) and non-repudiation (digital signatures) issuer signs a certificate
If you only want to check if a mail is not altered: use digital signature!
Proves that the signature was provided by the intended signer
trust anchor = public key that has been verified and that’s trusted
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Digital signatures
- no modifications allowed - identity can be derived
- Works with a one-way hash (message digest), like SHA- 1 (512 bit blocks) or MD5 (128 bits digest) or HMAC that uses a key
- Acceptable encryption algorithms choices – DSA, RSA, ECDSA
HASH it and ENCRYPT message digest
Correct way to create and use a digital signature
– hash the document, encrypt only the hash with the sender’s private key, send both the plain text document and the encrypted hash to recipient.
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S/Mime
Confidentiality (encryption) Integrity (using PKCS X.509 PKI) and non-rep through signed message digests PEM - Privacy Enhanced Email Encryption (AES) PKI X.509 and RSA
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Message Security protocol
Military X.400. Sign, Encrypt, Hash
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Pretty Good Privacy (PGP)
uses IDEA and RSA instead
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Digital Certificates
contain specific identifying information and their construction is governed by international standard (X.509), creation and validation of digital certificates
Who signs a digital certificate – someone vouching for person not the person.
CRLs - Certificate Revocation Lists are maintained by the various certificate authorities and contain the serial numbers of certificates that have been issued by a CA and have been revoked along with the date and time the revocation went into effect.
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Hashing
ATTACK HASH BY BRUTE FORCE and dictionary CRYPTANALYSIS
Basic Technique –
BRUTE Force will win with no constraints input of any length and generate a fixed length output Hash algorithms (Message Digests)
Requirements for HASH
- works on non-fixed length input
- must be relatively easy to compute for any input
- function must be one way
- function must be one way
Most used are MD5 (message Digest 128 bits) and SHA1 (signature hashing algorithm 160 bits)
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MD5
It also processes 512-bit blocks of the message, but it uses four distinct rounds of computation to produce a digest of the same length as the MD2 and MD4 algorithms (128 bits).
MD5 has the same padding requirements as MD4— the message length must be 64 bits less than a multiple of 512 bits.
MD5 implements additional security features that reduce the speed of message digest production significantly.
Unfortunately, recent cryptanalytic attacks demonstrated that the MD5 protocol is subject to collisions, preventing its use for ensuring message integrity.
It is possible to create two digital certificates from different public keys that have the same MD5 hash.
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SHA1
Was designed by NIST and NSA to be used in digital signatures
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Traffic analysis
Inference of information from analysis of traffic
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Traffic padding
generation of spurious data units
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Collision
Same message digest as a result of hashing.
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Ciphertext Only
attacker sees only the ciphertext, one of the most difficult
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Known Plaintext
attacker knowns both cipher and plaintext
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Chosen Plaintext
offline attack (attacker prepares list of plaintexts) -lunch box attack
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online attack
(attacker chooses the plaintext based on the ciphertext already received)
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Chosen ciphertext
attacker chooses both the plaintext values and the ciphertext values, cherry picking, feed info and based on what you learned get key
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Birthday Attack
Collisions appear much fasters, birthdays match
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POODLE
- (Padding Oracle on Downgraded Legacy Encryption) attack helped force the movement from SSL 3.0 to TLS because it allowed attackers to easily access SSL encrypted messages.
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CRIME/BEAST
earlier attacks against SSL
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STUXNET
worm aimed at Iranian nuclear capability
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Digital Rights Management
uses encryption to enforce copyright restrictions on digital media. serves to bring U.S. copyright law into compliance with terms of two
World Intellectual Property Organization (WIPO) treaties. The first major provision of the DMCA is the prohibition of attempts to circumvent copyright protection mechanisms placed on a protected work by the copyright holder.
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Applets
these code objects are sent from a server to a client to perform some action. In fact, applets are actually self-contained miniature programs that execute independently of the server that sent them.
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Java applets
are simply short Java programs transmitted over the Internet to perform operations on a remote system.
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ActiveX
Controls are Microsoft’s answer to Sun’s Java applets.
Operate in a similar fashion, but they are implemented using a variety of languages(C, C + +, Java).
Two key distinctions between Java applets and ActiveX controls.
First, ActiveX controls use proprietary Microsoft technology and, therefore, can execute only on systems running Microsoft browsers.
Second, ActiveX controls are not subject to the sandbox restrictions placed on Java applets.
They have full access to the Windows operating environment and can perform a number of privileged actions
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Natural environment threats
earthquakes
floods,
tornadoes
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Supply system threats
power
communications
water
gas
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Man-made threats
vandalism, fraud, theft
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Politically motivated threats
terroristic attacks,
riots
bombings
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Layered defense model
all physical controls should be work together in a tiered architecture (stacked layers)
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Vulnerability
weakness
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threat
someone will identify the weakness and use it against you and becomes the threat agent
Risk analysis-->Acceptable
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Kerchoff principle
a cryptographic system should be secure even if everything about the system, except the key, is public knowledge
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Input and Parameter Checking
limit how much data can be proffered as input. Proper data validation is the only way to do away with buffer overflows.
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Side-channel attack
a passive, noninvasive attack intended to observe the operation of a device.
When the attack is successful, the attacker is able to learn valuable information contained within the smartcard, such as an encryption key
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Transitive Trust
Transitive trust is the concept that if A trusts B and B trusts C, then A inherits trust of C through the transitive property— which works like it would in a mathematical equation: if a = b, and b = c, then a = c.
A transitive trust extends the trust relationship between the two security domains to all of their subdomains.
Within the context of least privilege, it’s important to examine these trust relationships.
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Nontransitive trust
Exists between two security domains, which could be within the same organization or between different organizations.
It allows subjects in one domain to access objects in the other domain.
A non-transitive trust enforces the principle of least privilege and grants the trust to a single domain at a time.
Interference
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Clean
no interference
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Line noise
can be EMI or RFI
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Transient
short duration of noise
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Countermeasures: Interference
voltage regulators, grounding/shielding and line conditioners
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COMMON mode noise
difference between hot and ground
HINT: common--grounds
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Traverse mode noise
difference between hot and neutral
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SPIKE
short high voltage
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SURGE
long high voltage
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Countermeasures: Excess voltage
surge protector
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FAULT
short outage
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BLACKOUT
long outage
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Countermeasures: Power loss
Backup power
Long term: Backup Power generator
Short term: UPS
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SAG/DIP
short low voltage
270
BROWNOUT
long low voltage
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Countermeasures: Power degredation
constant voltage transformers
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Humidity
<40% static electricity up to 20.000 volts NORMAL 40-60% up to 4000 volts >60% corrosion
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Tempest
Shielding and other emanations-reducing mechanism, a technology that allows the electronic emanations that every monitor produces (known as Van Eck radiation) to be read from a distance (this process is known as Van Eck phreaking)
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White noise
broadcasting false traffic at all times to mask and hide the presence of real emanations.
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Faraday cage
A box, mobile room, or entire building designed with an external metal skin, often a wire mesh that fully surrounds an area on all sides (in other words, front, back, left, right, top, and bottom).
This metal skin acts as an EMI absorbing capacitor control zone - the implementation of either a Faraday cage or white noise generation or both to protect a specific area in an environment
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Fire Prevention
Training
| construction, supplies, reach ability
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Manual Fire Detection
pull boxes
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Automatic Fire Detection
Automatic dial- up: Fire department, aka Auxiliary station alarm
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Types of Fire detectors
- Smoke activated,
- Heat activated,
- Flame activated (infrared)
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Common Fire
WATER, SODA ACID (take away temp)
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Liquids Fire
GAS/CO2, SODA ACID (takes away fuel)
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Electrical Fire
-GAS/CO2 (displace O2)
283
Metals Fire
DRY POWDER
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WATER
suppress temperature
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SODA ACID
reduces fuel supply
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CO2
reduces oxygen
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HALON
chemical reaction
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Wet pipe sprinkler
always contains water, fuse nozzle melts at 165F
289
Dry pipe sprinkler
water in tank until clapper valve releases it
- only begins to fill when triggered by excessive heat
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Halon replacements
FM-200 most common replacement (others: CEA, NAF, FE-13 Argon INERGEN Low Pressure Water
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TPM
Trusted Platform Module is both a specification for a cryptoprocessor chip on a mainboard and the general name for implementation of the specification.
A TPM chip is used to store and process cryptographic keys for the purposes of a hardware supported/ implemented hard drive encryption system.
Generally, a hardware implementation, rather than a software-only implementation of hard drive encryption, is considered to be more secure.
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Constrained or restricted interface
implemented within an application to restrict what users can do or see based on their privileges.
Natural
