IT SECURITY

SOFTWARE ATTACKS by
Virus
A virus is a type of malicious software (malware) comprised of small pieces of code attached to legitimate programs. When that program runs, the virus runs.
Viruses are malicious programs that spread throughout computer files without user knowledge. Most widespread virus infections spread through email message attachments that activate when opened. The vicious cycle of a virus perpetuates as infected emails are forwarded to multiple users. Viruses also spread through shared media, such as Universal Serial Bus (USB) drives.

Initially created as pranks, viruses are responsible for widespread and significant computer system and file destruction. Installing anti-virus software helps prevent, block or remove previously installed viruses
 Worm
A worm is a type of malicious software (malware) that replicates while moving across computers, leaving copies of itself in the memory of each computer in its path.
A worm locates a computer’s vulnerability and spreads within its connected network like an infection, while continually seeking new vulnerabilities. Like viruses, worms often originate from e-mail attachments that appear to be from trusted senders. Worms then spread to a user’s contacts via his e-mail account and address book.
Some worms spread and then do nothing while tthers cause harm. In such cases, the worm’s code is known as payload.


 Malicious Software (Malware)
Malicious software, commonly known as malware, is any software that brings harm to a computer system. Malware can be in the form of worms, viruses, trojans, spyware, adware and rootkits, etc., which steal protected data, delete documents or add software not approved by a user.




Malware is software designed to cause harm to a computer and user. Some forms of malware “spy” on user Internet traffic. Examples include spyware and adware. Spyware monitors a user’s location and if enabled, it can capture sensitive information, e.g., credit card numbers, promoting identity theft. Adware also acquires user information, which is shared with advertisers and then integrated with unwanted, triggered pop-up ads.
Worms and viruses behave differently, as they can quickly proliferate and undermine an entire computer system. They also may perform unsavory activities from a user’s computer without the user’s knowledge. In the wake of a virus or worm, a computer system can experience significant damage.
Anti-malware should determine if there are threats by scanning a computer and removing them, if found. Prevention is better than corrective action after infection. Although anti-virus programs should be continually enabled and updated, certain types of threats, like spyware, often make their way into a computer system.
At all times, a firewall should be in place for additional security. Multiple, compatible protective sources are encouraged as additional insurance against malware.
Adware
Adware is free computer software that contains commercial advertisements. Adware programs include games, desktop toolbars or utilities. Commonly, adware is Web-based and collects Web browser data to target advertisements, especially pop-ups.
Adware is also known as freeware and pitchware.
Adware is categorized as follows:
Legitimate: Free or trial product sponsored advertisements
Spyware: Tracks user website preferences and compromises privacy
Adware may appear innocuous and provide users with legitimate business software but then unleash spyware that collects browser search data for targeted user-specific advertisements.
Uninstalling adware generally requires anti-adware software. A variety of free and paid versions are available, but licensed adware is the most reliable, aggressive and recommended. Anti-adware software is also included in virus scanning packages.
Trojan Horse
A Trojan horse is a seemingly benign program that when activated, causes harm to a computer system.
A Trojan horse is also known as a Trojan virus or Trojan.
The Trojan horse is named for ancient Greece’s apparent gift of peace to the Trojans, when a giant wooden horse was secretly filled with Greek warriors. After the Trojans allowed the horse to enter their great city, the Greek warriors emerged from the horse gained control of the city of Troy.
The following are types of trojan horses:
Backdoor Trojan: opens a back door for a user to access a victim’s system at a later time
Downloader: This Trojan downloads malicious software and causes harm to the victim’s computer system.
Infostealer: This Trojan attempts to steal information from the victim’s computer.
Remote Access Trojan (RAT): This can be hidden in games or other programs of a smaller variety and give the attacker control of the victim’s computer.
Data Sending Trojan: This gives the perpetrator sensitive information like passwords or other information programmed to be hijacked.
Destructive Trojan: This destroys the victim’s files.
Proxy Trojan: As a proxy server, this allows the attacker to hijack a victim’s computer and conduct illegal activities from the victim’s computer.
Spyware
Spyware is infiltration software that secretly monitors unsuspecting users. It can enable a hacker to obtain sensitive information, such as passwords, from the user's computer. Spyware exploits user and application vulnerabilities and is often attached to free online software downloads or to links that are clicked by users.
Peer-to-peer (P2P) file sharing has increased the proliferation of spyware and its ramifications.
Anti-spyware applications locate and remove spyware and are recommended as a preventative line of defense against infiltration and damage.
Anti-virus software removes PC viruses, but anti-virus scans do not always detect spyware. Spyware and cookies are similar, but spyware conducts infiltration activity continuously until it is removed by specific anti-spyware tools.
Users should take the following precautions to prevent spyware attacks:
Maintain anti-virus and anti-spyware updates and patches.
Download from well-known and reputable sites only.
Use a firewall for enhanced security



Internet Bot
An Internet bot, in its most generic sense, is software that performs an automated task over the Internet. More specifically, a bot is an automated application used to perform simple and repetitive tasks that would be time-consuming, mundane or impossible for a human to perform.

Bots can be used for productive tasks, but they are also frequently used for malicious purposes.

The term "bot" comes from robot. An Internet bot may also be known as a Web robot or WWW robot.
One of the best examples of a good bot is a search engine spider. Such bots troll the Web and index new pages for a search engine. Other examples include the original Internet relay chat bots and chatterbots.

Malicious bots are typically blended threats that come as part virus/worm, part bot and are used in a identity theft or to launch denial of service attacks. This is especially prevalent in a botnet, which is a grouping of computers that are all infected with a malicious bot. Other illegal, or at least questionable uses, involve bots that harvest email addresses for spam, scrape content or manipulate comments/votes on sites that allow user feedback.

Rootkit
A rootkit is software used by a hacker to gain constant administrator-level access to a computer or network. A rootkit is typicially installed through a stolen password or by exploiting a system vulnerabilities without the victim's consent or knowledge.
Rootkits primarily aim at user-mode applications, but they also focus on a computer’s hypervisor, the kernel, or even firmware. Rootkits can completely deactivate or destroy the anti-malware software installed in an infected computer, thus making a rootkit attack difficult to track and eliminate. When done well, the intrusion can be carefully concealed so that even system administrators are unaware of it.
Rootkits may be also presented as a Trojan or even as a hidden file along with a seemingly harmless file. This can be a graphic or even a silly application distributed via email. When the victim clicks the program or graphic, the rootkits are installed on their system without their knowledge.
Some of the impacts of rootkits are often to:
Provide the attacker with complete backdoor access, permitting them to falsify or steal documents.
Hide other malware, especially keyloggers. The keyloggers may then be used to access and steal the victim's sensitive data.
Enable the attacker to use the infected machine as a zombie computer to trigger attacks on others


Spoofing
Spoofing, in general, is a fraudulent or malicious practice in which communication is sent from an unknown source disguised as a source known to the receiver. Spoofing is most prevalent in communication mechanisms that lack a high level of security.
Email spoofing is one of the best known spoofs. Since core SMTP fails to offer authentication, it is simple to forge and impersonate emails. Spoofed emails may request personal information and may appear to be from a known sender. Such emails request the recipient to reply with an account number for verification. The email spoofer then uses this account number for identity theft purposes, such as accessing the victim's bank account, changing contact details and so on.
The attacker (or spoofer) knows that if the recipient receives a spoofed email that appears to be from a known source, it is likely to be opened and acted upon. So a spoofed email may also contain additional threats like Trojans or other viruses. These programs can cause significant computer damage by triggering unexpected activities, remote access, deletion of files and more.