1

Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

  • Upload
    others

  • View
    0

  • Download
    0

Embed Size (px)

Citation preview

Page 1: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Ujjwal Kumar IT Department Gaya College, Gaya

Page 2: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Malware also called as malicious software is any software intentionally designed to cause damage to a computer, server, client, or computer network

A wide variety of malware types exist, including computer viruses, worms, Trojan horses,ransomware, spyware, adware, rogue software, and scareware.

A range of antivirus software, firewalls and other strategies are used to help protect against the introduction of malware, to help detect it if it is already present, and to recover from malware-associated malicious activity and attacks

Ujjwal Kumar IT Department Gaya College, Gaya

Page 3: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

The term "virus" is also misused by extension to refer to other types of malware. "Malware" encompasses computer viruses along with many other forms of malicious software, such as computer "worms", ransomware, spyware, adware, trojan horses, keyloggers, and other malicious software.

The majority of active malware threats are trojan horse programs or computer worms rather than computer viruses.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 4: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

A computer virus is a program designed to harm or cause harm on an infected computer. Its spreads through e-mail attachments, portable devices, websites containing malicious scripts and file downloads.

A computer virus attaches itself to the host files and always activate whenever you open the infected files.

The virus can replicate itself and then infect the other files on your computer causing more damage.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 5: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

A memory-resident virus (or simply "resident virus") installs itself as part of the operating system when executed, after which it remains in RAM from the time the computer is booted up to when it is shut down.

Resident viruses overwrite interrupt handling code or other functions, and when the operating system attempts to access the target file or disk sector, the virus code intercepts the request and redirects the control flow to the replication module, infecting the target.

In contrast, a non-memory-resident virus (or "non-resident virus"), when executed, scans the disk for targets, infects them, and then exits (i.e. it does not remain in memory after it is done executing).

Ujjwal Kumar IT Department Gaya College, Gaya

Page 6: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Non-resident computer viruses are executable. Therefore, unless a non-resident computer virus is set to run on startup, shutting down or restarting your computer will stop it.

The only way for a non-resident virus to carry out its malicious effects is through execution.

In comparison, resident computer viruses don’t require manual execution. A resident computer virus will stay within your computer’s RAM where it’s able to perform its malicious activities at any time. As long as your computer is running, it will use RAM, in which case the resident computer virus will remain active.

Some types of resident computer viruses are designed to quickly spread, in which case they can infect other computers or devices on your business’s network in a short period.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 7: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Email Virus Macro Browser Hijacker Boot Sector Web Scripting Virus Multipartite polymorphic virus File infector virus

Ujjwal Kumar IT Department Gaya College, Gaya

Page 8: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

An email virus consists of malicious code that is distributed in email messages, and it can be activated when a user clicks on a link in an email message, opens an email attachment or interacts in some other way with the infected email message.

Email viruses often spread by causing the attachment or malicious message to be sent to everyone in the victim's address book.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 9: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

These viruses infect the files created using some applications or programs that contain macros such as doc, pps, xls and mdb. They automatically infect the files with macros and also templates and documents that are contained in the file.

They hide in documents shared through e-mail and networks.

Macro viruses are written in the same macro language used for software applications.

Such viruses spread when you open an infected document, often through email attachments.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 10: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Browser hijacking is a form of unwanted software that modifies a web browser's settings without a user's permission, to inject unwanted advertising into the user's browser.

A browser hijacker may replace the existing home page, error page, or search engine with its own.

These are generally used to force hits to a particular website, increasing its advertising revenue.

This virus can spread in many different ways including a voluntary download.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 11: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Traditional Virus that infect the boot sector on storage devices.

By putting its code in the boot sector, a virus can guarantee it gets executed load itself into memory immediately, and it is able to run whenever the computer is on.

This type of virus can take control when you start — or boot — your computer.

One way it can spread is by plugging an infected storage device into your computer.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 12: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Most web pages include some complex codes in order to create an interactive and interesting content.

Such a code is often exploited to cause certain undesirable actions. They mostly originate from the infected web pages or browsers.

This type of virus exploits the code of web browsers and web pages. If you access such a web page, the virus can infect your computer.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 13: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

These type of viruses spread in many different ways. Their actions vary depending on the OS installed and presence of certain files.

They tend to hide in the computer’s memory but do not infect the hard disk.

This kind of virus infects and spreads in multiple ways. It can infect both program files and system sectors.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 14: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

They encode or encrypt themselves in a different way every time they infect your computer.

They use different encryption algorithms. This makes it difficult for the antivirus

software to locate them.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 15: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

This common virus inserts malicious code into executable files.

These files used to perform certain functions or operations on a system.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 16: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Some more types of Malicious Software

Ujjwal Kumar IT Department Gaya College, Gaya

Page 17: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

This program is very similar to a virus and has the ability to self-replicate leading to negative effects on your computer.

A copy of the worm scans the network for another machine that has a specific security hole. It copies itself to the new machine using the security hole, and then starts replicating from there, as well.

They are often designed to exploit the file transmission capabilities found on many computers.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 18: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Many worms use multiple methods to spread across networks, including the following: Email: Carried inside files sent as email attachments Internet: Via links to infected websites; generally hidden in the website’s

HTML, so the infection is triggered when the page loads Downloads & FTP Servers: May initially start in downloaded files or

individual FTP files, but if not detected, can spread to the server and thus all outbound FTP transmissions

Instant Messages (IM): Transmitted through mobile and desktop messaging apps, generally as external links, including native SMS apps, WhatsApp, Facebook messenger, or any other type of ICQ or IRC message

P2P/Filesharing: Spread via P2P file sharing networks, as well as any other shared drive or files, such as a USB stick or network server

Networks: Often hidden in network packets; though they can spread and self-propagate through shared access to any device, drive or file across the network

Ujjwal Kumar IT Department Gaya College, Gaya

Page 19: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Ransomware is a type of malware from cryptovirology that threatens to publish the victim's data or perpetually block access to it unless a ransom is paid.

While some simple ransomware may lock the system in a way which is not difficult for a knowledgeable person to reverse, more advanced malware uses a technique called cryptoviralextortion, in which it encrypts the victim's files, making them inaccessible, and demands a ransom payment to decrypt them.

In a properly implemented cryptoviral extortion attack, recovering the files without the decryption key is an intractable problem and difficult to trace digital currencies such as Ukash or Bitcoin and other cryptocurrency are used for the ransoms, making tracing and prosecuting the perpetrators difficult.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 20: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

In computing, a Trojan horse, or trojan,is any malware which misleads users of its true intent.

The term is derived from the Ancient Greek story of the deceptive Trojan Horse that led to the fall of the city of Troy.

Trojans are made for destruction, or some kind of loss to its victim.

Trojans may allow an attacker to access users' personal information such as banking information, passwords, or personal identity.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 21: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

It can also delete a user's files or infect other devices connected to the network.

Ransomware attacks are often carried out using a trojan.

Unlike computer viruses, worms, and rogue security software, trojans generally do not attempt to inject themselves into other files or otherwise propagate themselves

Ujjwal Kumar IT Department Gaya College, Gaya

Page 22: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Spyware describes software with malicious behaviour that aims to gather information about a person or organization and send such information to another entity in a way that harms the user; for example by violating their privacy or endangering their device's security.

This behaviour may be present in malware as well as in legitimate software.

Websites may also engage in spyware behaviours like web tracking.

Web tracking is the practice by which operators of websites collect, store and share information about visitors’ activities on the World Wide Web

Hardware devices may also be affected.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 23: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Scareware is a form of malware which uses social engineering to cause shock, anxiety, or the perception of a threat in order to manipulate users into buying unwanted software.

The "scareware" label can also apply to any application or virus which pranks users with intent to cause anxiety or panic.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 24: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Rogue security software is a form of malicious software and internet fraud that misleads users into believing there is a virus on their computer and aims to convince them to pay for a fake malware removal tool that actually installs malware on their computer.

It is a form of scareware that manipulates users through fear, and a form of ransomware.

Rogue security software has been a serious security threat in desktop computing

Ujjwal Kumar IT Department Gaya College, Gaya

Page 25: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Adware, often called advertising-supported software by its developers, is software that generates revenue for its developer by automatically generating online advertisements in the user interface of the software or on a screen presented to the user during the installation process.

The software may generate two types of revenue: one is for the display of the advertisement and another on a "pay-per-click" basis, if the user clicks on the advertisement.

Some advertisements also act as spyware, collecting and reporting data about the user, to be sold or used for targeted advertising or user profiling. The software may implement advertisements in a variety of ways, including a static box display, a banner display, full screen, a video, pop-up ad or in some other form. All forms of advertising carry health, ethical, privacy and security risks for users.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 26: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Ujjwal Kumar IT Department Gaya College, Gaya

Virus

Scareware

Page 27: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Once a virus has successfully attached to a program, file, or document, the virus will lie dormant until circumstances cause the computer or device to execute its code.

In order for a virus to infect your computer, you have to run the infected program, which in turn causes the virus code to be executed.

This means that a virus can remain dormant on your computer, without showing major signs or symptoms.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 28: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

However, once the virus infects your computer, the virus can infect other computers on the same network.

Stealing passwords or data, logging keystrokes, corrupting files, and even taking over your machine are just some of the devastating and irritating things a virus can do.

While some viruses can be playful in intent and effect, others can have profound and damaging effects.

This includes erasing data or causing permanent damage to your hard disk. Worse yet, some viruses are designed with financial gains in mind.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 29: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

In a constantly connected world, you can contract a computer virus in many ways, some more obvious than others.

Viruses can be spread through email and text message attachments, Internet file downloads, and social media scam links.

Your mobile devices and smartphones can become infected with mobile viruses through shady app downloads.

Viruses can hide disguised as attachments of socially shareable content such as funny images, greeting cards, or audio and video files.

To avoid contact with a virus, it’s important to exercise caution when surfing the web, downloading files, and opening links or attachments.

To help stay safe, never download text or email attachments that you’re not expecting, or files from websites you don’t trust.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 30: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

A computer virus attack can produce a variety of symptoms. Here are some of them:

Frequent pop-up windows. Pop-ups might encourage you to visit unusual sites. Or they might prod you to download antivirus or other software programs.

Changes to your homepage.Your usual homepage may change to another website, for instance. Plus, you may be unable to reset it.

Mass emails being sent from your email account. A criminal may take control of your account or send emails in your name from another infected computer.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 31: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Frequent crashes. A virus can inflict major damage on your hard drive. This may cause your device to freeze or crash. It may also prevent your device from coming back on.

Unusually slow computer performance. A sudden change of processing speed could signal that your computer has a virus.

Unknown programs that start up when you turn on your computer.You may become aware of the unfamiliar program when you start your computer. Or you might notice it by checking your computer’s list of active applications.

Unusual activities like password changes. This could prevent you from logging into your computer.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 32: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

The many types of computer viruses and their effects are very harmful and can completely damage your system.

Here are some of the things you can do to help keep your computer safe.

Make sure you perform certain tasks like: Updates Anti-Viruses with multiple secure areas like securing

web, files, devices etc. More secure operating systems

Unix/Linux Based OS

Ujjwal Kumar IT Department Gaya College, Gaya

Page 33: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Avoid clicking on any pop-up advertisements. Always scan your email attachments before

opening them. Always scan the files that you download

using file sharing programs Use trusted networks for connections. Regular monitoring of online works.

Ujjwal Kumar IT Department Gaya College, Gaya

Page 34: Ujjwal Kumar IT Department Gaya College, Gaya · 2021. 1. 13. · Ujjwal Kumar IT Department Gaya College, Gaya. Ujjwal Kumar IT Department Gaya College, Gaya. Virus Scareware Once

Ujjwal Kumar IT Department Gaya College, Gaya