Flaw exploitation attacks exploit a flaw in the target system's software in order to cause a processing failure or to cause it to exhaust system resources. An example of such a processing failure is the 'ping of death' attack. This attack involved sending an unexpectedly large ping packet to certain Windows systems. The target system could not handle this abnormal packet, and a system crash resulted. With respect to resource exhaustion attacks, the resources targeted include CPU time, memory, disk space, space in a special buffer, or network bandwidth. In many cases, simply patching the software can circumvent this type of DOS attack.

Brute force attacks are performed with tools that cycle through many possible character, number, and symbol combinations to guess a password. Pg 134 Shon Harris CISSP All-In-One Certification Exam Guide. Since the token allows offline checking of PIN, the cracker can keep trying PINS until it is cracked.

From the glossary of Computer Security Basics:
The Bell-LaPadula model is the security policy model on which the Orange Book requirements are based. From the Orange Book definition, "A formal state transition model of computer security policy that describes a set of access control rules. In this formal model, the entities in a computer system are divided into abstract sets of subjects and objects. The notion of secure state is defined and it is proven that each state transition preserves security by moving from secure state to secure state; thus, inductively proving the system is secure. A system state is defined to be 'secure' if the only permitted access modes of subjects to objects are in accordance with a specific security policy. In order to determine whether or not a specific access mode is allowed, the clearance of a subject is compared to the classification of the object and a determination is made as to whether the subject is authorized for the specific access mode."
The Biba Model is an integrity model of computer security policy that describes a set of rules. In this model, a subject may not depend on any object or other subject that is less trusted than itself.
The Clark Wilson Model is an integrity model for computer security policy designed for a commercial environment. It addresses such concepts as nondiscretionary access control, privilege separation, and least privilege. TEMPEST is a government program that prevents the compromising electrical and electromagnetic signals that emanate from computers and related equipment from being intercepted and deciphered.
Source: RUSSEL, Deborah & GANGEMI, G.T. Sr., Computer Security Basics, O'Reilly,
1991.
Also: U.S. Department of Defense, Trusted Computer System Evaluation Criteria (Orange
Book), DOD 5200.28-STD. December 1985 (also available here).

MAC provides high security by regulating access based on the clearance of individual users and sensitivity labels for each object. Clearance levels and sensitivity levels cannot be modified by individual users -- for example, user Joe (SECRET clearance) cannot reclassify the "Presidential Doughnut Recipe" from "SECRET" to "CONFIDENTIAL" so that his friend Jane (CONFIDENTIAL clearance) can read it. The administrator is ultimately responsible for configuring this protection in accordance with security policy and directives from the Data Owner.
DAC is incorrect. In DAC, the data owner is responsible for controlling access to the object.
Access control matrix is incorrect. The access control matrix is a way of thinking about the access control needed by a population of subjects to a population of objects. This access control can be applied using rules, ACL's, capability tables, etc.
TACACS is incorrect. TACACS is a tool for performing user authentication.
References:
CBK, p. 187, Domain 2: Access Control.
AIO3, Chapter 4, Access Control.