Definitions and Terms in Security Testing and Software Engineering
@Note: Although All terms & definitions are already available on respective wiki page, I am re-writing them for the sake of just making an online note to track my reading history.
- Malware = Malicious Software
- Malware is a software used or created to disrupt computer operation, gather sensitive information, or gain access to private computer systems. It can appear in the form of code, scripts, active content, and other software. 'Malware' is a general term used to refer to a variety of forms of hostile, intrusive, or annoying software.
- Computer Virus
- A computer virus is a computer program that can replicate itself and spread from one computer to another. The term "virus" is also commonly, but erroneously, used to refer to other types of malware, including but not limited to adware and spyware programs that do not have a reproductive ability.
- Spyware
- Spyware is a type of malware (malicious software) installed on computers that collects information about users without their knowledge. The presence of spyware is typically hidden from the user and can be difficult to detect. Some spyware, such as keyloggers, may be installed by the owner of a shared, corporate, or public computer intentionally in order to monitor users.
- Adware
- Adware or advertising-supported software is any software package which automatically renders advertisements. These advertisements can be in the form of a popup. They may also be in the user interface of the software or on a screen presented to the user during the installation process. The object of the Adware is to generate revenue for its author. Adware, by itself, is harmless; however, some adware may come with integrated spyware such as keyloggers and other privacy-invasive software.
- Computer worm
- A computer worm is a standalone malware computer program that replicates itself in order to spread to other computers. Often, it uses a computer network to spread itself. This is due to security shortcomings on the target computer. Unlike a computer virus, it does not need to attach itself to an existing program. Worms almost always cause at least some harm to the network, even if only by consuming bandwidth, whereas viruses almost always corrupt or modify files on a targeted computer.
- Trojan horse (computing)
- A Trojan horse, or Trojan, is a type of malware that masquerades as a legitimate file or helpful program possibly with the purpose of granting a hacker unauthorized access to a computer. Trojans do not attempt to inject themselves into other files like a computer virus. Trojan horses may steal information, or harm their host computer systems. Trojans may use drive-by downloads or install via online games or internet-driven applications in order to reach target computers. The term is derived from the Trojan Horse story in Greek mythology because Trojan horses employ a form of “social engineering,” presenting themselves as harmless, useful gifts, in order to persuade victims to install them on their computers.
- Firewall (computing)
- A firewall can either be software-based or hardware-based and is used to help keep a network secure. Its primary objective is to control the incoming and outgoing network traffic by analyzing the data packets and determining whether it should be allowed through or not, based on a predetermined rule set. A network's firewall builds a bridge between an internal network that is assumed to be secure and trusted, and another network, usually an external (inter)network, such as the Internet, that is not assumed to be secure and trusted.
- Zombie (computer science)
- In computer science, a zombie is a computer connected to the Internet that has been compromised by a hacker, computer virus or trojan horse and can be used to perform malicious tasks of one sort or another under remote direction. Botnets of zombie computers are often used to spread e-mail spam and launch denial-of-service attacks. Most owners of zombie computers are unaware that their system is being used in this way. Because the owner tends to be unaware, these computers are metaphorically compared to zombies.
- Email spam
- Email spam, also known as junk email or unsolicited bulk email (UBE), is a subset of electronic spam involving nearly identical messages sent to numerous recipients by email. Clicking on links in spam email may send users to phishing web sites or sites that are hosting malware. Spam email may also include malware as scripts or other executable file attachments. Definitions of spam usually include the aspects that email is unsolicited and sent in bulk. One subset of UBE is UCE (unsolicited commercial email). The opposite of "spam", email which one wants, is called "ham", usually when referring to a message's automated analysis (such as Bayesian filtering). Like other forms of unwanted bulk messaging, it is named for Spam luncheon meat by way of a Monty Python sketch in which Spam is depicted as ubiquitous and unavoidable.


