Viruses, Trojans, & worms, oh my: The basics on malware

http://arstechnica.com/security/2013/02/viruses-trojans-and-worms-oh-my-the-basics-on-malware/     / post-PC world malware major problem home computer users businesses steal information upload computers controlled by hackers critical systems US power plants infected with malware spread by USB drives Dexter stole credit card data from point-of-sale terminals at business espionage-motivated computer threats Online Security infect affect computers viruses worms, Trojans ransomware replicate themselves spread from computer to computer targeting deleting data stealing information attached to an executable file not be active or able to spread until a user runs or opens the malicious host file or program Cisco notes host code is executed, the viral code is executed as well normally, the host program keeps functioning after it is infected by the virus overwrite other programs with copies of themselves destroys the host program viruses spread software or document they are attached to is transferred from one computer to another using the network, a disk, file sharing, or infected e-mail attachments worm operates more or less independently of other files, whereas a virus depends on a host program to spread itself entire computer networks destructive worms ever unleashed on the Internet was dubbed Slammer Trojans do not replicate themselves Trojan horse of ancient Troy because they disguise themselves as legitimate, harmless programs to convince users to install them activated, it can achieve any number of attacks on the host irritating the user popping up windows or changing desktops damaging the host deleting files stealing data activating spreading other malware such as viruses create back doors to give malicious users access to the system attacks combine attributes blended threats that may spread more effectively and be harder to defend against sub-categories backdoor remote access Trojan information stealer ransomware rootkit botnet hack hacking hacker sneak attack access infected system bypassing security undocumented OS network functions innocent-looking phishing e-mails Recruitment Plan Excel file embedded Adobe Flash file installed the backdoor Outlook object executed by Microsoft Excel targeting  vulnerability allowing the execution of code Poison Ivy backdoor connects back to servers operated by malicious users attacker has full remote access to the infected workstation full access to network drives that the user can access Remote Access Trojan RAT malicious administrative tool root access compromised machine user interface client component attacker can use to issue commands to the server component residing in the compromised machine keyloggers desktop recorders and memory scrapers steal passwords financial credentials proprietary data advantage monetize encrypt the PC’s data to prevent the user from accessing it locking the user out of the whole system threatening destruction of the machine with a Trojan HTML JavaScript markup programming languages that power much of the Web Java attacks browsers visiting  malicious website legitimate website infected by hackers drive-by downloads infect exploit exploits vulnerabilities in a browser or plugin updates patch vulnerabilities bugs spam e-mail attachment downloading download infected file from the Internet User Account Control to prevent applications from installing without user consent Defenses address space layout randomization data execution prevention exploit vulnerabilities /