CISSP (Chapter 10 - Software Development Security) Flashcards
An application is downloaded from the Internet to perform disk cleanup and to delete unnecessary temporary files. The application is also recording network login data and sending them to another party. This application is best described as which of the following? A. A virus B. A Trojan horse C. A worm D. A logic bomb
B. A Trojan horse looks like an innocent and helpful program, but in the background it is carrying out some type of malicious activity unknown to the user. The Trojan horse could be corrupting files, sending the user’s password to an attacker, or attacking another computer
What is the importance of inference in an expert system?
A. The knowledge base contains facts, but must also be able to combine facts to derive new information and solutions.
B. The inference machine is important to fight against multipart viruses.
C. The knowledge base must work in units to mimic neurons in the brain.
D. The access must be controlled to prevent unauthorized access.
A. The whole purpose of an expert system is to look at the data it has to work with and what the user presents to it and to come up with new or different solutions. It basically performs data-mining activities, identifies patterns and relationships the user can’t see, and provides solutions. This is the same reason you would go to a human expert. You would give her your information, and she would combine it with the information she knows and give you a solution or advice, which is not necessarily the same data you gave her
A system has been patched many times and has recently become infected with a dangerous virus. If antivirus software indicates that disinfecting a file may damage it, what is the correct action?
A. Disinfect the file and contact the vendor.
B. Back up the data and disinfect the file.
C. Replace the file with the file saved the day before.
D. Restore an uninfected version of the patched file from backup media.
D. Some files cannot be properly sanitized by the antivirus software without destroying them or affecting their functionality. So, the administrator must replace such a file with a known uninfected file. Plus, the administrator needs to make sure he has the patched version of the file, or else he could be introducing other problems. Answer C is not the best answer because the administrator may not know the file was clean yesterday, so just restoring yesterday’s file may put him right back in the same boat
What is the purpose of polyinstantiation?
A. To restrict lower-level subjects from accessing low-level information
B. To make a copy of an object and modify the attributes of the second copy
C. To create different objects that will react in different ways to the same input
D. To create different objects that will take on inheritance attributes from their class
B. Instantiation is what happens when an object is created from a class. Polyinstantiation is when more than one object is made and the other copy is modified to have different attributes. This can be done for several reasons. The example given in the chapter was a way to use polyinstantiation for security purposes to ensure that a lower-level subject could not access an object at a higher level
Database views provide what type of security control? A. Detective B. Corrective C. Preventive D. Administrative
C. A database view is put into place to prevent certain users from viewing specific data. This is a preventive measure, because the administrator is preventing the users from seeing data not meant for them. This is one control to prevent inference attacks.
Which of the following is used to deter database inference attacks?
A. Partitioning, cell suppression, and noise and perturbation
B. Controlling access to the data dictionary
C. Partitioning, cell suppression, and small query sets
D. Partitioning, noise and perturbation, and small query sets
A. Partitioning means to logically split the database into parts. Views then dictate what users can view specific parts. Cell suppression means that specific cells are not viewable by certain users. And noise and perturbation is when bogus information is inserted into the database to try to give potential attackers incorrect information
When should security first be addressed in a project? A. During requirements development B. During integration testing C. During design specifications D. During implementation
A. The trick to this question, and any one like it, is that security should be implemented at the first possible phase of a project. Requirements are gathered and developed at the beginning of a project, which is project initiation. The other answers are steps that follow this phase, and security should be integrated right from the beginning instead of in the middle or at the end
Online application systems that detect an invalid transaction should do which of the following?
A. Roll back and rewrite over original data.
B. Terminate all transactions until properly addressed.
C. Write a report to be reviewed.
D. Checkpoint each data entry.
C. This can seem like a tricky question. It is asking you if the system detected an invalid transaction, which is most likely a user error. This error should be logged so it can be reviewed. After the review, the supervisor, or whoever makes this type of decision, will decide whether or not it was a mistake and investigate it as needed. If the system had a glitch, power fluctuation, hang-up, or any other software- or hardware-related error, it would not be an invalid transaction, and in that case the system would carry out a rollback function
Which of the following are rows and columns within relational databases? A. Rows and tuples B. Attributes and rows C. Keys and views D. Tuples and attributes
D. In a relational database, a row is referred to as a tuple, whereas a column is referred to as an attribute.
Databases can record transactions in real time, which usually updates more than one database in a distributed environment. This type of complexity can introduce many integrity threats, so the database software should implement the characteristics of what’s known as the ACID test. Which of the following are incorrect characteristics of the ACID test?
i. Atomicity Divides transactions into units of work and ensures that all modifications take effect or none take effect.
ii. Consistency A transaction must follow the integrity policy developed for that particular database and ensure all data are consistent in the different databases.
iii. Isolation Transactions execute in isolation until completed, without interacting with other transactions.
iv. Durability Once the transaction is verified as inaccurate on all systems, it is committed and the databases cannot be rolled back.
A. i, ii
B. ii. iii
C. ii, iv
D. iv
D. The following are correct characteristics of the ACID test:
• Atomicity Divides transactions into units of work and ensures that all modifications take effect or none take effect. Either the changes are committed or the database is rolled back.
• Consistency A transaction must follow the integrity policy developed for that particular database and ensure all data are consistent in the different databases.
• Isolation Transactions execute in isolation until completed without interacting with other transactions. The results of the modification are not available until the transaction is completed.
• Durability Once the transaction is verified as accurate on all systems, it is committed and the databases cannot be rolled back.
The software development life cycle has several phases. Which of the following lists these phases in the correct order?
A. Project initiation, system design specifications, functional design analysis and planning, software development, installation/implementation, operational/maintenance, disposal
B. Project initiation, functional design analysis and planning, system design specifications, software development, installation/implementation, operational/maintenance, disposal
C. Project initiation, functional design analysis and planning, software development, system design specifications, installation/implementation, operational/maintenance, disposal
D. Project initiation, system design specifications, functional design analysis and planning, software development, operational/maintenance
B. The following outlines the common phases of the software development life cycle:
- Project initiation
- Functional design analysis and planning
- System design specifications
- Software development
- Testing
- Installation/implementation
- Operational/maintenance
- Disposal
John is a manager of the application development department within his company. He needs to make sure his team is carrying out all of the correct testing types and at the right times of the development stages. Which of the following have the best descriptions of the types of software testing that should be carried out?
i. Unit testing Individual component is in a controlled environment where programmers validate data structure, logic, and boundary conditions.
ii. Integration testing Verifying that components work together as outlined in design specifications.
iii. Acceptance testing Ensuring that the code meets customer requirements.
iv. Regression testing After a change to a system takes place, retesting to ensure functionality, performance, and protection.
A. i, ii
B. ii, iii
C. i, ii, iv
D. i, ii, iii, iv
D. There are different types of tests the software should go through because there are different potential flaws we will be looking for. The following are some of the most common testing approaches:
• Unit testing Individual component is in a controlled environment where programmers validate data structure, logic, and boundary conditions.
• Integration testing Verifying that components work together as outlined in design specifications.
• Acceptance testing Ensuring that the code meets customer requirements.
• Regression testing After a change to a system takes place, retesting to ensure functionality, performance, and protection.
Tim is a software developer for a financial institution. He develops middleware software code that carries out his company’s business logic functions. One of the applications he works with is written in the C programming language and seems to be taking up too much memory as it runs over a period of time. Which of the following best describes what Tim should implement to rid this software of this type of problem? A. Bounds checking B. Garbage collector C. Parameter checking D. Compiling
B. Garbage collection is an automated way for software to carry out part of its memory management tasks. A garbage collector identifies blocks of memory that were once allocated but are no longer in use and deallocates the blocks and marks them as free. It also gathers scattered blocks of free memory and combines them into larger blocks. It helps provide a more stable environment and does not waste precious memory. Some programming languages, such as Java, perform automatic garbage collection; others, such as C, require the developer to perform it manually, thus leaving opportunity for error.
Marge has to choose a software development model that her team should follow. The application that her team is responsible for developing is a critical application that can have little to no errors. Which of the following best describes the type of model her team should follow? A. Cleanroom B. Joint Analysis Development (JAD) C. Rapid Application Development (RAD) D. Reuse Model
A. The software development models and their definitions are as follows:
• Joint Analysis Development (JAD) A method that uses a team approach in application development in a workshop-oriented environment.
• Rapid Application Development (RAD) A method of determining user requirements and developing systems quickly to satisfy immediate needs.
• Reuse Model A model that approaches software development by using progressively developed models. Reusable programs are evolved by gradually modifying pre-existing prototypes to customer specifications. Since the Reuse model does not require programs to be built from scratch, it drastically reduces both development cost and time.
• Cleanroom An approach that attempts to prevent errors or mistakes by following structured and formal methods of developing and testing. This approach is used for high-quality and critical applications that will be put through a strict certification process.
\_\_\_\_\_\_\_\_\_\_ is a software testing technique that provides invalid, unexpected, or random data to the input interfaces of a program. A. Agile testing B. Structured testing C. Fuzzing D. EICAR
C. Fuzz testing or fuzzing is a software testing technique that provides invalid, unexpected, or random data to the input interfaces of a program. If the program fails (for example, by crashing or failing built-in code assertions), the defects can be noted.
