ASSIGNMENT
Topic : malware, spyware, trojan horse
submitte by
Salini. S
physical science
MALWARE
Introduction
Malware is any software intentionally designed to cause damage to a computer, server, client, or computer network. Malware is a contraction for “malicious software.” It 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 does the damage after it is implanted or introduced in some way into a target's computer and can take the form of directly executable code, scripts, so-called "active content", and other forms of data. Some kinds of malware are largely referred to in the media as computer viruses, worms, Trojan horses, ransomware, spyware, adware and scareware among other terms. Malware has a malicious intent, acting against the interest of the computer user and so does not include software that causes unintentional harm due to some deficiency, which is typically described as a software bug.
Today, malware is used primarily to steal sensitive personal, financial, or business information for the benefit of others. Malware is sometimes used broadly against government or corporate websites to gather guarded information or to disrupt their operation in general. However, malware is often used against individuals to gain personal information such as social security numbers, bank or credit card numbers and so on.
Types of Malware
- Viruses
- Spyware
- Trojan horse
Virus
Virus is a subgroup of malware. A virus is malicious software attached to a document or file that supports macros to execute its code and spread from host to host. Once downloaded, the virus will lay dormant until the file is opened and in use. Viruses are designed to disrupt a system’s ability to operate. As a result, viruses can cause significant operational issues and data loss. It is a program or piece of code that is loaded on to your computer without your knowledge and runs against your wishes. Viruses can also replicate themselves. All computer viruses are manmade. Viruses copy themselves to other disks to spread to other computers. They can be merely annoying or they can be vastly destructive to your files. Viruses can enter to your computer as an attachment of images, greeting, or audio / video files. Viruses also enters through downloads on the Internet. They can be hidden in free or trial software or other files that you download. So before you download anything from internet is sure about it first. Almost all viruses are attached to an executable file, which means the virus may exist on your computer but it actually cannot infect your computer unless you run or open the malicious program. It is important to note that a virus cannot be spread without a human action, such as running an infected program to keep it going.
Examples of computer viruses
- Macro virus
- Boot virus
- Logic Bomb virus
- Directory virus
- Resident virus
Spyware
Spyware is a type of malware 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. Spyware programs lurk on your computer to steal important information, like your passwords and logins and other personal identification information and then send it off to someone else.
Spyware is malicious software that runs secretly on a computer and reports back to a remote user. Rather than simply disrupting a device’s operations, spyware targets sensitive information and can grant remote access to predators. Spyware is often used to steal financial or personal information. A specific type of spyware is a key logger, which records your keystrokes to reveal passwords and personal information.
Any software can be classified as spyware if it is downloaded without the user's authorization. Spyware is controversial because even when it is installed for relatively innocuous reasons, it can violate the end user's privacy and has the potential to be abused.
Spyware can be difficult to detect; often, the first indication a user has that a computing device has been infected with spyware is a noticeable reduction in processor or network connection speeds and in the case of mobile devices -- data usage and battery life. Anti-spyware tools can be used to prevent or remove spyware. Anti-spyware tools can either provide real-time protection by scanning network data and blocking malicious data, or detect and remove spyware already on a system by executing scans.
To prevent spyware, users should only download software from trusted sources, read all disclosures when installing software, avoid clicking on pop-up ads and stay current with updates and patches for browser , operating system and application software. To reduce the probability of infection, network administrators should practice the principle of least privilege (POLP) and require remote workers to access network resources over a virtual private network (VPN) that runs a security scan before granting access privileges.
Trojan horses
A Trojan horse is not a virus. It is a destructive program that looks as a genuine application. Unlike viruses, Trojan horses do not replicate themselves but they can be just as destructive. Trojans also open a backdoor entry to your computer which gives malicious users/programs access to your system, allowing confidential and personal information to be theft.
A Trojan horse program has the appearance of having a useful and desired function. A Trojan horse neither replicates nor copies itself, but causes damage or compromises the security of the computer. A Trojan horse must be sent by someone or carried by another program and may arrive in the form of a joke program or software of some sort. These are often used to capture your logins and passwords.
Trojan viruses are disguised as helpful software programs. But once the user downloads it, the Trojan virus can gain access to sensitive data and then modify, block or delete the data. This can be extremely harmful to the performance of the device. Unlike normal viruses and worms, Trojan viruses are not designed to self-replicate.
A Trojan horse is a harmful program that misrepresents itself to masquerade as a regular, benign program or utility in order to persuade a victim to install it. A Trojan horse usually carries a hidden destructive function that is activated when the application is started. The term is derived from the Ancient Greek story of the Trojan horse used to invade the city of Troy by stealth.
Trojan horses are generally spread by some form of social engineering, for example, where a user is duped into executing an e-mail attachment disguised to be unsuspicious (e.g. : a routine form to be filled in) or by drive-by download. Although their payload can be anything, many modern forms act as a backdoor, contacting a controller which can then have unauthorized access to the affected computer. While Trojan horses and backdoors are not easily detectable by themselves, computers may appear to run slower due to heavy processor or network usage.
Examples of Trojan horses
- Remote Access Trojans
- Data Sending Trojans
- Destructive Trojans
- Proxy Trojans
- FTP Trojans
- Disabler Security software Trojans
- Denial-of-service attack Trojans
