- (Topic 1)
Rule-Based Access Control (RuBAC) access is determined by rules. Such rules would fit within what category of access control ?
Correct Answer:C
Rule-based access control is a type of non-discretionary access control because this access is determined by rules and the subject does not decide what those rules will be, the rules are uniformly applied to ALL of the users or subjects.
In general, all access control policies other than DAC are grouped in the category of non- discretionary access control (NDAC). As the name implies, policies in this category have rules that are not established at the discretion of the user. Non-discretionary policies establish controls that cannot be changed by users, but only through administrative action.
Both Role Based Access Control (RBAC) and Rule Based Access Control (RuBAC) fall within Non Discretionary Access Control (NDAC). If it is not DAC or MAC then it is most likely NDAC.
IT IS NOT ALWAYS BLACK OR WHITE
The different access control models are not totally exclusive of each others. MAC is making use of Rules to be implemented. However with MAC you have requirements above and beyond having simple access rules. The subject would get formal approval from management, the subject must have the proper security clearance, objects must have labels/sensitivity levels attached to them, subjects must have the proper security clearance. If all of this is in place then you have MAC.
BELOW YOU HAVE A DESCRIPTION OF THE DIFFERENT CATEGORIES:
MAC = Mandatory Access Control
Under a mandatory access control environment, the system or security administrator will define what permissions subjects have on objects. The administrator does not dictate user??s access but simply configure the proper level of access as dictated by the Data Owner.
The MAC system will look at the Security Clearance of the subject and compare it with the object sensitivity level or classification level. This is what is called the dominance relationship.
The subject must DOMINATE the object sensitivity level. Which means that the subject must have a security clearance equal or higher than the object he is attempting to access.
MAC also introduce the concept of labels. Every objects will have a label attached to them indicating the classification of the object as well as categories that are used to impose the need to know (NTK) principle. Even thou a user has a security clearance of Secret it does not mean he would be able to access any Secret documents within the system. He would be allowed to access only Secret document for which he has a Need To Know, formal approval, and object where the user belong to one of the categories attached to the object.
If there is no clearance and no labels then IT IS NOT Mandatory Access Control.
Many of the other models can mimic MAC but none of them have labels and a dominance relationship so they are NOT in the MAC category.
NISTR-7316 Says:
Usually a labeling mechanism and a set of interfaces are used to determine access based on the MAC policy; for example, a user who is running a process at the Secret classification should not be allowed to read a file with a label of Top Secret. This is known as the ??simple security rule,?? or ??no read up.?? Conversely, a user who is running a process with a label of Secret should not be allowed to write to a file with a label of Confidential. This rule is called the ??*-property?? (pronounced ??star property??) or ??no write down.?? The *- property is required to maintain system security in an automated environment. A variation on this rule called the ??strict *-property?? requires that information can be written at, but not above, the subject??s clearance level. Multilevel security models such as the Bell-La Padula Confidentiality and Biba Integrity models are used to formally specify this kind of MAC policy.
DAC = Discretionary Access Control
DAC is also known as: Identity Based access control system.
The owner of an object is define as the person who created the object. As such the owner has the discretion to grant access to other users on the network. Access will be granted based solely on the identity of those users.
Such system is good for low level of security. One of the major problem is the fact that a user who has access to someone's else file can further share the file with other users without the knowledge or permission of the owner of the file. Very quickly this could become the wild wild west as there is no control on the dissimination of the information.
RBAC = Role Based Access Control
RBAC is a form of Non-Discretionary access control.
Role Based access control usually maps directly with the different types of jobs performed by employees within a company.
For example there might be 5 security administrator within your company. Instead of creating each of their profile one by one, you would simply create a role and assign the administrators to the role. Once an administrator has been assigned to a role, he will IMPLICITLY inherit the permissions of that role.
RBAC is great tool for environment where there is a a large rotation of employees on a daily basis such as a very large help desk for example.
RBAC or RuBAC = Rule Based Access Control RuBAC is a form of Non-Discretionary access control.
A good example of a Rule Based access control device would be a Firewall. A single set of rules is imposed to all users attempting to connect through the firewall.
NOTE FROM CLEMENT:
Lot of people tend to confuse MAC and Rule Based Access Control.
Mandatory Access Control must make use of LABELS. If there is only rules and no label, it cannot be Mandatory Access Control. This is why they call it Non Discretionary Access control (NDAC).
There are even books out there that are WRONG on this subject. Books are sometimes opiniated and not strictly based on facts.
In MAC subjects must have clearance to access sensitive objects. Objects have labels that contain the classification to indicate the sensitivity of the object and the label also has categories to enforce the need to know.
Today the best example of rule based access control would be a firewall. All rules are imposed globally to any user attempting to connect through the device. This is NOT the case with MAC.
I strongly recommend you read carefully the following document:
NISTIR-7316 at http://csrc.nist.gov/publications/nistir/7316/NISTIR-7316.pdf
It is one of the best Access Control Study document to prepare for the exam. Usually I tell people not to worry about the hundreds of NIST documents and other reference. This document is an exception. Take some time to read it.
Reference(s) used for this question:
KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 33.
and
NISTIR-7316 at http://csrc.nist.gov/publications/nistir/7316/NISTIR-7316.pdf and
Conrad, Eric; Misenar, Seth; Feldman, Joshua (2012-09-01). CISSP Study Guide (Kindle Locations 651-652). Elsevier Science (reference). Kindle Edition.
- (Topic 5)
Which of the following offers security to wireless communications?
Correct Answer:B
Wireless Transport Layer Security (WTLS) is a communication protocol that allows wireless devices to send and receive encrypted information over the Internet. S- WAP is not defined. WSP (Wireless Session Protocol) and WDP (Wireless Datagram Protocol) are part of Wireless Access Protocol (WAP).
Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 4: Cryptography (page 173).
- (Topic 5)
The primary purpose for using one-way hashing of user passwords within a password file is which of the following?
Correct Answer:B
The whole idea behind a one-way hash is that it should be just that - one- way. In other words, an attacker should not be able to figure out your password from the hashed version of that password in any mathematically feasible way (or within any reasonable length of time).
Password Hashing and Encryption
In most situations , if an attacker sniffs your password from the network wire, she still has some work to do before she actually knows your password value because most systems hash the password with a hashing algorithm, commonly MD4 or MD5, to ensure passwords are not sent in cleartext.
Although some people think the world is run by Microsoft, other types of operating systems are out there, such as Unix and Linux. These systems do not use registries and SAM
databases, but contain their user passwords in a file cleverly called ??shadow.?? Now, this shadow file does not contain passwords in cleartext; instead, your password is run through a hashing algorithm, and the resulting value is stored in this file.
Unixtype systems zest things up by using salts in this process. Salts are random values added to the encryption process to add more complexity and randomness. The more randomness entered into the encryption process, the harder it is for the bad guy to decrypt and uncover your password. The use of a salt means that the same password can be encrypted into several thousand different formats. This makes it much more difficult for an attacker to uncover the right format for your system.
Password Cracking tools
Note that the use of one-way hashes for passwords does not prevent password crackers from guessing passwords. A password cracker runs a plain-text string through the same one-way hash algorithm used by the system to generate a hash, then compares that generated has with the one stored on the system. If they match, the password cracker has guessed your password.
This is very much the same process used to authenticate you to a system via a password. When you type your username and password, the system hashes the password you typed and compares that generated hash against the one stored on the system - if they match, you are authenticated.
Pre-Computed password tables exists today and they allow you to crack passwords on Lan Manager (LM) within a VERY short period of time through the use of Rainbow Tables. A Rainbow Table is a precomputed table for reversing cryptographic hash functions, usually for cracking password hashes. Tables are usually used in recovering a plaintext password up to a certain length consisting of a limited set of characters. It is a practical example of a space/time trade-off also called a Time-Memory trade off, using more computer processing time at the cost of less storage when calculating a hash on every attempt, or less processing time and more storage when compared to a simple lookup table with one entry per hash. Use of a key derivation function that employs a salt makes this attack unfeasible.
You may want to review "Rainbow Tables" at the links: http://en.wikipedia.org/wiki/Rainbow_table http://www.antsight.com/zsl/rainbowcrack/
Today's password crackers:
Meet oclHashcat. They are GPGPU-based multi-hash cracker using a brute-force attack (implemented as mask attack), combinator attack, dictionary attack, hybrid attack, mask
attack, and rule-based attack.
This GPU cracker is a fusioned version of oclHashcat-plus and oclHashcat-lite, both very well-known suites at that time, but now deprecated. There also existed a now very old oclHashcat GPU cracker that was replaced w/ plus and lite, which - as said - were then merged into oclHashcat 1.00 again.
This cracker can crack Hashes of NTLM Version 2 up to 8 characters in less than a few hours. It is definitively a game changer. It can try hundreds of billions of tries per seconds on a very large cluster of GPU's. It supports up to 128 Video Cards at once.
I am stuck using Password what can I do to better protect myself?
You could look at safer alternative such as Bcrypt, PBKDF2, and Scrypt.
bcrypt is a key derivation function for passwords designed by Niels Provos and David Mazi??res, based on the Blowfish cipher, and presented at USENIX in 1999. Besides incorporating a salt to protect against rainbow table attacks, bcrypt is an adaptive function: over time, the iteration count can be increased to make it slower, so it remains resistant to brute-force search attacks even with increasing computation power.
In cryptography, scrypt is a password-based key derivation function created by Colin Percival, originally for the Tarsnap online backup service. The algorithm was specifically designed to make it costly to perform large-scale custom hardware attacks by requiring large amounts of memory. In 2012, the scrypt algorithm was published by the IETF as an Internet Draft, intended to become an informational RFC, which has since expired. A simplified version of scrypt is used as a proof-of-work scheme by a number of cryptocurrencies, such as Litecoin and Dogecoin.
PBKDF2 (Password-Based Key Derivation Function 2) is a key derivation function that is part of RSA Laboratories' Public-Key Cryptography Standards (PKCS) series, specifically PKCS #5 v2.0, also published as Internet Engineering Task Force's RFC 2898. It replaces an earlier standard, PBKDF1, which could only produce derived keys up to 160 bits long.
PBKDF2 applies a pseudorandom function, such as a cryptographic hash, cipher, or HMAC to the input password or passphrase along with a salt value and repeats the process many times to produce a derived key, which can then be used as a cryptographic key in subsequent operations. The added computational work makes password cracking much more difficult, and is known as key stretching. When the standard was written in 2000, the recommended minimum number of iterations was 1000, but the parameter is intended to
be increased over time as CPU speeds increase. Having a salt added to the password reduces the ability to use precomputed hashes (rainbow tables) for attacks, and means that multiple passwords have to be tested individually, not all at once. The standard recommends a salt length of at least 64 bits.
The other answers are incorrect:
"It prevents an unauthorized person from trying multiple passwords in one logon attempt." is incorrect because the fact that a password has been hashed does not prevent this type of brute force password guessing attempt.
"It minimizes the amount of storage required for user passwords" is incorrect because hash algorithms always generate the same number of bits, regardless of the length of the input. Therefore, even short passwords will still result in a longer hash and not minimize storage requirements.
"It minimizes the amount of processing time used for encrypting passwords" is incorrect because the processing time to encrypt a password would be basically the same required to produce a one-way has of the same password.
Reference(s) used for this question: http://en.wikipedia.org/wiki/PBKDF2
http://en.wikipedia.org/wiki/Scrypt
http://en.wikipedia.org/wiki/Bcrypt
Harris, Shon (2012-10-18). CISSP All-in-One Exam Guide, 6th Edition (p. 195) . McGraw- Hill. Kindle Edition.
- (Topic 1)
What is called the act of a user professing an identity to a system, usually in the form of a log-on ID?
Correct Answer:B
Identification is the act of a user professing an identity to a system, usually in the form of a log-on ID to the system.
Identification is nothing more than claiming you are somebody. You identify yourself when you speak to someone on the phone that you don??t know, and they ask you who they??re speaking to. When you say, ??I??m Jason.??, you??ve just identified yourself.
In the information security world, this is analogous to entering a username. It??s not analogous to entering a password. Entering a password is a method for verifying that you are who you identified yourself as.
NOTE: The word "professing" used above means: "to say that you are, do, or feel something when other people doubt what you say". This is exactly what happen when you provide your identifier (identification), you claim to be someone but the system cannot take your word for it, you must further Authenticate to the system to prove who you claim to be.
The following are incorrect answers:
Authentication: is how one proves that they are who they say they are. When you claim to be Jane Smith by logging into a computer system as ??jsmith??, it??s most likely going to ask you for a password. You??ve claimed to be that person by entering the name into the username field (that??s the identification part), but now you have to prove that you are really that person.
Many systems use a password for this, which is based on ??something you know??, i.e. a secret between you and the system.
Another form of authentication is presenting something you have, such as a driver??s license, an RSA token, or a smart card.
You can also authenticate via something you are. This is the foundation for biometrics. When you do this, you first identify yourself and then submit a thumb print, a retina scan, or another form of bio-based authentication.
Once you??ve successfully authenticated, you have now done two things: you??ve claimed to be someone, and you??ve proven that you are that person. The only thing that??s left is for the
system to determine what you??re allowed to do.
Authorization: is what takes place after a person has been both identified and authenticated; it??s the step determines what a person can then do on the system.
An example in people terms would be someone knocking on your door at night. You say, ??Who is it???, and wait for a response. They say, ??It??s John.?? in order to identify themselves. You ask them to back up into the light so you can see them through the peephole. They do so, and you authenticate them based on what they look like (biometric). At that point you decide they can come inside the house.
If they had said they were someone you didn??t want in your house (identification), and you then verified that it was that person (authentication), the authorization phase would not include access to the inside of the house.
Confidentiality: Is one part of the CIA triad. It prevents sensitive information from reaching the wrong people, while making sure that the right people can in fact get it. A good example is a credit card number while shopping online, the merchant needs it to clear the transaction but you do not want your informaiton exposed over the network, you would use a secure link such as SSL, TLS, or some tunneling tool to protect the information from prying eyes between point A and point B. Data encryption is a common method of ensuring confidentiality.
The other parts of the CIA triad are listed below:
Integrity involves maintaining the consistency, accuracy, and trustworthiness of data over its entire life cycle. Data must not be changed in transit, and steps must be taken to ensure that data cannot be altered by unauthorized people (for example, in a breach of confidentiality). In addition, some means must be in place to detect any changes in data that might occur as a result of non-human-caused events such as an electromagnetic pulse (EMP) or server crash. If an unexpected change occurs, a backup copy must be available to restore the affected data to its correct state.
Availability is best ensured by rigorously maintaining all hardware, performing hardware repairs immediately when needed, providing a certain measure of redundancy and failover, providing adequate communications bandwidth and preventing the occurrence of bottlenecks, implementing emergency backup power systems, keeping current with all necessary system upgrades, and guarding against malicious actions such as denial-of- service (DoS) attacks.
Reference used for this question:
http://whatis.techtarget.com/definition/Confidentiality-integrity-and-availability-CIA http://www.danielmiessler.com/blog/security-identification-authentication-and-authorization http://www.merriam-webster.com/dictionary/profess
KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 36.
- (Topic 6)
Which of the following is an IP address that is private (i.e. reserved for internal networks, and not a valid address to use on the Internet)?
Correct Answer:A
This is a valid Class A reserved address. For Class A, the reserved addresses are 10.0.0.0 - 10.255.255.255.
The following answers are incorrect:
11.0.42.5 Is incorrect because it is not a Class A reserved address.
12.0.42.5 Is incorrect because it is not a Class A reserved address.
13.0.42.5 Is incorrect because it is not a Class A reserved address.
The private IP address ranges are defined within RFC 1918: RFC 1918 private ip address range
C:\Users\MCS\Desktop\1.jpg References:
3Com http://www.3com.com/other/pdfs/infra/corpinfo/en_US/501302.pdf
AIOv3 Telecommunications and Networking Security (page 438)