Section 2: Malware Flashcards
What is a malware?
Software designed to infiltrate a computer system and possibly damage it without the user’s knowledge or consent.
- Viruses
- Worms
- Trojans
- Ransomware
- Spyware
- Rootkits
- Spam
What is a Virus?
A malicious code that runs on a machine without the user’s knowledge and infects the computer when executed.
- requires user’s action in order to reproduce and spread
What are the 10 types of viruses?
- Boot Sector Virus
- Macro Virus
- Program Virus
- Multipartite Virus
- Encrypted Virus
- Polymorphic Virus
- Metamorphic Virus
- Stealth Virus
- Armoured Virus
- Hoax Virus
What is a Boot Sector Virus?
Virus that is stored in the first sector of a hard drive and are loaded into memory upon boot up
- difficult to detect
- installed before OS boots up
- need specific AV that looks for boot sector viruses to find it
What is a Macro Virus?
Virus that is embedded into a document and is executed when the document is opened by a user
- Word / Power Point / Excel
- macros are not malicious by themselves, they are used to do many useful functions in short periods of time
- Excel for example, can have a macro code that makes calculations faster. But because you can add code to that macro, bad guys can take advantage of this and add malicious code
What is a Program Virus?
A virus that infects an executable or an application
- Every time you open an application or execute the program, you load the virus
What is a Multipartite Virus?
Combination of Boot Sector virus and Program virus. Attaches itself to the boot sector and system files before attacking other files on the computer
- allows for persistence
- you can find the program virus within windows, but not find the boot sector. Every time you reboot, it will reinstall into windows again
What is an Encrypted Virus?
A virus that uses a cipher to encrypt its contents to avoid detection by any AV
What is a Polymorphic Virus?
An advanced version of an encrypted virus that changes itself every time it is executed by altering the decryption module to avoid detection
- morphs the way its code looks so that a signature-based AV cannot detect it anymore
What is a Metamorphic Virus?
Virus that is able to rewrite itself entirely before it attempts to infect a file (advanced version of a polymorphic virus)
What is a Stealth Virus?
It is a sub category of viruses who have mechanisms to stay undetected/protect themselves
- Encrypted, Polymorphic, Metamorphic
What is an Armoured Virus?
A virus that has a layer of protection to confuse a program or person analysing it
What is a Hoax Virus?
Not necessarily a virus, but instead you get a virus that is trying to trick a user into infecting their own machine
- message or website popup
- phone call from someone pretending to work for Microsoft (“follow these steps to remove virus”)
- “install this type of software to get rid of the virus”
- allowing remote access to your machine
What is a Worm?
A piece of malicious software, like a virus, but is able to replicate and spread without user interaction
- they take advantage of security holes in OS
- can move from victim to victim, network to network, and across the world
- can cause disruption to network traffic and computing activities
- can cause a system to crash
What does a Worm use within a system?
- Computing power
- Processing power
- Memory
- Network traffic