Domain 5: Identity and Access Management Flashcards
What is Access?
Flow of information between a subject and an object
What is an Access Control?
It is a security feature that controls how subjects and objects communicate and interact with other systems and resources.
What is Object?
Passive entity that contains information (computer, database, file, program) that is accessed by a subject.
Centralised administration: Approaches to Administration
One element responsible for configuring access controls. Only modified through central administration, very strict control.
Decentralised administration: Approaches to Administration
Access to information is controlled by owners or creators of information. There may be a lack of consistency with regards to procedures, as it is difficult to form a system wide view of all user access at any given time
Hybrid: Approaches to Administration
Centralised control is exercised for some infomation and decentralised for other information
IAAA
Four key principles upon which access control relies:
- Identification
- Authentication
- Authorisation
- Accountability
Explain the principle of Identification/Assertion
This is about ensuring a subject is who he says he is. It binds a user to the appropriate controls based on the unique user instance. This may also include Registration which is about verifying an individual’s identity and adds a unique idenfier to an identity system.
Explain the principle of Authentication
Process of verifying the user where the user provides private data and establishes trust between the user and the system for the allocation of privileges.
Explain the principle of Authorisation
Checks the resources user is allowed to access. These resources must be defined and monitored.
Explain the principle of Accountability
Who was responsible for an action? Logging is the best way to provide accountability, where change log for approved changes and change management process is captured.
Relationship between Identity, Authentication, and Authorisation
- Identification provides uniquness
- Authentication provides validity
- Authorsiation provides control
Logical Access Controls
Tools used to administer IAAA
MAC Address
48 bit number, supposed to be globally unique, however, can be spoofed by software and no longer acts as a strong ID or authentication.
SSO
Single Sign On. It is also referred to as Reduced Sign On or federated ID management.
SSO Advantages
Ability to use stronger passwords, easier administration, and less time to access resources
SSO Disadvantages
Once a key is compromised, all resources can be accessed. Similarly, if DB is compromised all PWs are compromised. A thin client is also a SSO approach.
Kerberos
Kerberos is a network authentication protocol. It is designed to provide strong authentication for client/server applications by using symmetric keys. Additionally, it addresses confidentiality, integrity, and authentication.
Benefits of Kerberos
Inexpensive, supported by a number of OS’s and is a mature protocol
Disadvantages of Kerberos
Takes time to administer, can be bottleneck or single point of failure
What is ‘Realm’?
Indicates an authentication administrative domain. Its intention is to establish the boundaries within which an authentication server has the authority to authenticate a user, host, or service. Uses symmetric Key cryptography.
KDC
The Key Distribution Centre grants tickets to client for specific servers. It knows all secret keys of all clients and servers from the network, TGS and AS. However, acts as a single point of failure.
AS
Authentication Server
TGS
Ticket Granting Server
Explain the Kerberos logon process
- The user types a username and password into the client
- The client encrypts the username with AES for transfer to the KDC.
- The KDC verifies the username against a database of known credentials.
- The KDC generates a symmetric key that will be used by the client and the Kerberos server. It encrypts this with a hash of the user’s password. The KDC also generates an encrypted time stamped TGT to the client.
- The client installs the TGT for use until it expires. The client also decrypts the symmetric key using a hash of the user’s password.
- Finally, the user can use this ticket to access to the desired service.
SESAME
Is a public key cryptology based authentication protocol. Its weakness is that it only authenticates first block and not the complete message. SESAME uses one ticket for authentication, while the other ticket is used for access privileges. This works with Privileged Attribute Certificates (PACS) and can use both symmetric and asymmetric encryption.
Logon scripting
Uses scripts to authenticate users
Directory service
A centralised database that includes information about subjects and objects. Hierarchical naming scheme, active directory has sophisticated security resources (group policy, user rights accounts, DNS services.
Type 1: Single Factor Authentication
Authentication factor is something you know, for example, password, PIN or passphrase
Type 2: Multi Factor Authentication
Something you have, such as physical devices that a user can use to provide authentication. Examples include smartcard, hardware token, smartcard, memory card, or USB drive.
Type 3: Multi Factor Authentication
Something you are, or something you do. It is a physical characteristic of a person identified with different types of biometrics, such as fingerprint or iris scans.
Type 1: Single Factor Authentication Examples
Passwords. A user can chose their own password, however, generally a longer password is a safer one.
Salting
A unique value is added to the end of the password to create a different hash value. This adds a layer of security to the hashing process, specifically against brute force attacks.
One Time Passwords
Can be one solution to increase security for type 1
Passphrase
Easiest to remember. This is converted to a virtual password by the system.
Cognitive password
Easy to remember like your mother’s maiden name
Hacking
Unauthorised access to password file
Brute force attack
Trying many different characters. This is an exhaustive attack
Dictionary attack
Trying common words in the dictionary
Social Engineering
Spoofing your identity to someone
Rainbow tables
Tables with passwords that are already in has formt, pre-hashed PW’s paired with high-speed look up functions