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CyberSecurity/Security Engineering

  • Tools, techniques and methods to support the development and maintenance of systems that can resist malicious attacks that are intended to damage a computer system or its data
  • Malicious software == Malware
  • this is a subfield of the broader field of computer security

Security Dimensions

  • Confidentiality
    • Information in a system may be disclosed or made accessible to people or programs that are not authorized to have access to that info.
  • Integrity
    • Information in a system may be damaged or corrupted making it unusual or unreliable.
  • Availability
    • Access to a system or its data that is normally available may not be possible

Security

  • The security of a system is a system property that reflects the sytems ability to protect itself from accidental or deliberate external attacks.
  • Security is essential as most systems are networked so that external access to the system through the internet is possible.
  • Security is an essential pre-requisite for avalibiltiy, reliability and safety.

Security Terminology

Know these definitions

  • Asset
    • Something of value which has to be protected.
  • Attack
    • An exploitation of a systems vulnerability. Generally, this is from outside the system and is a deliberate attempt to cause some damage.
  • Control
    • A protective measure that reduces a systems vulnerability. encryption is an example of control that reduces a vulnerabiltiy of weak access control system
  • Exposure
    • Possible loss or harm to a computing system. This can be loss or damage to data, or time and effor to recovery after a security breach.
  • Threat
    • Circumstances that have potential cuase loss or harm. (system vulnerabiltiy that is subjected to an attack)
  • Vulnerabiltiy
    • A weakness in a computer-based system that may be exploited to cause loss or harm.

Threat types (IMPORTANT)

Know these

  • Interception threats
    • Allows an attacker to gain access to an asset
  • Interruption threats
    • Allows an attacker to make part of the system unavailable.
    • A possible threat might be (DoS) Denial of Service
    • A possible threat might be (DDoS) Distributed Denial of Service
  • Modification Threats
    • Allow an attacker to tamper with system asset
    • E.g. attacker alters or destroys a user record
  • Fabrication threat
    • Allows an attacker to insert false information into a system
    • E.g. False transactions might be added to the system that trnasfers money to the perps bank account (or out of your bank account!)

Types of security requirements (IMPORTANT)

  • Identification
  • Authentication
  • Authorization
  • Immunity (i.e. protection)
  • Integrity
  • Intrustion Detection
  • Non-repudiation (i.e. undeniable)
  • Privacy
  • Security Auditing
  • System maintenance security

(these are all requirmenets)

Security requirement classification (IMPORTANT)

  • Risk:
    • Avoidance
      • risks that should be avoided by designing system so that hese risks cannot arise
    • Detection
      • Define mechanisms that identify risks if it does arise, and neutrilize the risk before loss
    • Mitigation
      • Set out how system should be designed so that it can recover from and restore sys. assets after loss has occurred

What is a bot? (IMPORTANT)

  • a bot is an automated software application that preforms reptitive tasks over a network.
    • It follows instructions to imitate human behavior but is faster and more accurate.
    • A bot can also run independenetly without human intervention
  • An org. or individual can use a bot to replace repetitive tasks.
  • Bots are super fast
  • They can also be malicous in the form of malware

Main Cybersecurity Threats (IMPORTANT)

know these definitions and what they are

  • Viruses
  • Worms
  • Trojan Horse
  • Social Engineering
  • Phishing
  • Ransomware
  • Pharming
  • Zombie Botnets
  • Rootkits
  • Man-in-the-middle (MITM)

Viruses

  • a virus is a program that spreads first by infecting files or system areas of a computer/networks hard drive.
    • it makes copies of itself and spreads to other computers (through attaching itself to programs, files, or the disk)
    • Some viruses are harmless and other may damage files, or destroy them.
      • (they're just computer programs that can be written to do malicous things.)
  • Unlike worms, viruses require user action
    • e.g. Opening email attachement or visiting a malicious web page

Worms

  • A worm is a type of virus that can spread Without human interaction
  • They spread from computer to computer taking up valuable memory and network bandwith, which can cause computers to stop working.
    • They do this by replicating itself and sending copies from computer to computer across network connections.
  • Worms can also allow attackers to gain access to your computer remotely (sort of a backdoor)

Trojan Horse

  • Trojan horse is a computer program that is hiding a virus or other malicious software.
    • It can be a program that looks like normal software and works normally but in the background its running malware on your computer as well
  • Usually obtained by downloading free games(or software) or as an email attachement
  • They tend to masquerade as a proper program while quietly destroying data or your system in the background

Social Engineering

  • While not having to directly relate to computer virueses or programs, it instead is a tactic of manipulating, influencing or deceiving a victim in order to gain control over a computer system/steal personal data.

Phishing

  • Phishing is when attackers send scam emails/texts that contain links to malicious websites, the websites may contain malware (such as ransomware).
    • An example of this is when UPS sends you text to confirm your order, you go to their website they sent you, fill your info, and suddenly you gave a bunch of your information to "UPS" which is really a hacker trying to collect your data and steal your credit card.
  • Counterfeit Emails are usually the most commmon method to do this, but texting is becoming more prevalent

(IMPORTANT)

The 4 phishing types are

  • Spear Phishing
  • Whaling
  • Vishing
  • Email Phising

Spear Phishing

  • Spear Phishing is a type of phishing attack that targets specific individuals or orgs. typically through malicous emails.
    • Goal is to steal sensitive info, such as login credentials, or infect the targets device with malware.

Whaling

  • This is a highly targeted phishing attack aimed at senior executives.
    • It pretends to be a legit email, but it digitally enableds fraud through social engineering to encourage victims to preform a secondary action
      • e.g. If you are a senior executive at a company, you may be asked to sign a contract that will allow the company to access your personal information
      • e.g. initiating a wire transfer of funds.

Vishing

  • Vishing or "voice phishing" involves defrauding people over the phone (also another social engineering tactic)
    • e.g. The IRS calls you because you didn't pay your taxs correctly (The IRS will never call you ever, unless you call them first!)
  • Usually done to get sensitive info out of you.

Email PHishing

  • The most common type is when attackers send scame emails/texts that contain links to malicous websites previously mentioned before

Ransomware

  • Type of malware which prevents you from accessing your device and the data stored on it, usually by encrypting your files.
    • A criminal group will then demand ransom in exchange for decryption, the computer data could become locked, encrypted, stolen or destroyed.

Two types of Ransomware

  • Crypto-Ransomware
    • Type of harmful program that encrypts files stored on a computer in order to extort for money.
  • Locker Ransomware
    • Type of Ransomware that doesn't use encryption, but instead it prevents the user from using their device.
    • The ransomeware will then display a message to the user that extorts fee to restore access to their device

Pharming

  • Sophistaticated type of fraudulent acitivty that redirects internet users to fake websites to steal data from them.
    • e.g. You go to amazon and it redirects you to a fake amazon that steals your info when you purchase an item (or login to your account)

Zombie Botnet

  • Botnets
    • They are a number of compromised computers used to create/send spam, viruses, or flood a network with messages as a (DoS) attack.
    • The compromised computers are called zombies
  • The malware usually includes a component that allwos the attacker to control the infected computer remotly, typically via a command-and-control-server
  • Once the botnet is established, the attacker can issue commands to zombie computers, directed them to prevorm various activities.
    • e.g. spam emails, DoS attacks, spreading malware, and helping botnet grow

Rootkit

  • Type of malware program that enables cyber criminals to gain access to machines without being detected
    • Commonly referred to as a "Backdoor"
  • Upon penetrating a computer, a hacker may install a collection of programs (called a rootkit)
  • This enables
    • Easy access for the hacker (and others) ionto the enterprise
    • Keystroke logger
  • Eliminates evidence of break-in
  • Modifies the OS

Man-in-the-Middle Attack (MITM)

  • This type of attack involves a threat actor putting themselves in the middle of two paries, typically a suer and an application to intercept their communications and data and use them for malicous purposes
    • e.g. When someone on a public network is packet sniffing for data that is unencrypted then using that data to login to your accounts

Dependable Programming guidlines

There are 8 of them (IMPORTANT)

  1. Limit visiblity of information in a program
  2. Check all inputs for validity
  3. Provide a handler for all exceptions
  4. Minimize the use of error-prone constructs
  5. Provide restart capabilities
  6. Check array bounds
  7. include timeouts when calling external components
  8. Name all constants that represent real-world values