Quick, plain-language definitions for common security threats.
MALmalware
Catch-all term for software designed to disrupt systems, steal data, or take control without permission.
payload -> execute -> compromise
ADSadware
Software that pushes ads aggressively and often tracks user behavior.
tracking id -> profile -> ad blast
TRJtrojan
Malicious software that pretends to be legitimate so users install it.
looks safe -> install -> hidden run
EYEshoulder surfing
Stealing sensitive information by watching someone type or view it.
user -> screen <- observer
PHIphishing
Deceptive messages that impersonate trusted senders to steal logins or data.
inbox -> fake login -> stolen creds
RANransomware
Malware that encrypts files or systems and demands payment for recovery.
files -> encrypted -> ransom note
SPYspyware
Software that secretly monitors activity and sends collected data to an operator.
collect -> beacon -> exfiltrate
0Dzero-day
A vulnerability exploited before the vendor releases a patch; attackers have zero days of warning.
new vuln -> no patch -> active exploit
BOTbotnet
A remotely controlled network of compromised devices used for coordinated abuse.
infected nodes -> c2 -> synchronized action
RKTrootkit
Stealthy software that hides deep in the OS to maintain persistent, privileged access.
kernel hook -> hide process -> persist
DDSDDoS
Distributed denial-of-service: flooding a target with traffic from many sources to overwhelm it.
botnet -> flood packets -> service down
SQLSQL injection
Inserting malicious SQL into application queries to read, modify, or delete database contents.
input -> ' OR 1=1 -- -> data leak
XSScross-site scripting
Injecting client-side scripts into web pages viewed by other users to steal sessions or data.
<script> -> victim browser -> stolen cookie
INSinsider threat
A trusted employee or contractor who misuses legitimate access to harm the organization.
trusted user -> abuse access -> exfiltrate
BRTbrute force
Systematically trying every possible password or key until the correct one is found.
wordlist -> try each -> match found
MiMman-in-the-middle
An attacker intercepts communication between two parties, reading or altering messages in transit.
A <-> [attacker] <-> B
ZMBzombie computer
A compromised machine controlled remotely as part of a botnet, usually without the owner knowing.
infected -> c2 beacon -> awaiting orders
WRMworm
Self-replicating malware that spreads across networks without user interaction.
exploit -> copy -> next host -> repeat
KEYkeylogger
Software or hardware that records every keystroke to capture passwords, messages, and sensitive input.
keypress -> log file -> exfiltrate
BDRbackdoor
A hidden method of bypassing normal authentication to gain remote access to a system.
hidden entry -> bypass auth -> remote shell
CRDcredential stuffing
Using stolen username/password pairs from one breach to log in to other services.
leaked creds -> try everywhere -> account takeover
SCHsupply-chain attack
Compromising a trusted vendor or dependency to distribute malicious code to downstream targets.
vendor -> inject payload -> all customers
ESCprivilege escalation
Exploiting a flaw to gain higher permissions than originally granted on a system.
low-priv user -> exploit -> root/admin
APTadvanced persistent threat
A prolonged, targeted cyberattack where an intruder maintains hidden access to steal data over time.
initial access -> persist -> exfil over months
SOCsocial engineering
Manipulating people through psychological tricks to reveal confidential information or perform actions.
trust -> manipulate -> access granted
Social engineering exploits human psychology rather than technical vulnerabilities. These are the most common attack patterns:
📧Phishing
Fraudulent emails impersonating trusted entities. Variants include spear-phishing (targeted), vishing (voice), smishing (SMS), and whaling (executives).
🍪Baiting
Leaving infected USB drives or offering free downloads to lure victims into executing malicious payloads.
🎭Pretexting
Creating a fabricated scenario (IT support, bank officer) to manipulate the target into revealing information.
🤝Quid Pro Quo
Offering a service or favor in exchange for information — e.g., fake tech support offering to “fix” your computer.
💧Water-Holing
Compromising a website frequently visited by the target group, infecting visitors automatically.
🚪Tailgating
Physically following an authorized person through a secure door or checkpoint without credentials.
🧠Mind Games
Exploiting urgency, empathy, and authority to bypass rational thinking and force immediate action.
Scammers leverage predictable mental shortcuts. Understanding these biases is the first line of defense:
Hyperbolic Discounting
People overvalue immediate rewards. Scammers use “act now” offers to short-circuit rational evaluation.
Habit
Routine actions bypass conscious thought. Attackers mimic familiar workflows (login pages, update prompts) to exploit autopilot.
Recency Effect
Recent events feel more important. A fake breach notification triggers panic because breaches are always in the news.
Halo Effect
One positive trait colors everything. A polished email from a “known brand” feels trustworthy even if the link is malicious.
Loss Aversion
Fear of losing something outweighs the desire to gain. “Your account will be suspended” is more compelling than “upgrade your plan.”
Ostrich Effect
Avoiding bad news. Victims ignore warning signs because confronting the problem feels worse than ignoring it.
Authority Bias
People comply with perceived authority figures. An email “from the CEO” gets fast, unquestioned action.
Optimism Bias
“It won’t happen to me.” This bias causes people to skip security steps they know they should follow.
Curiosity Effect
Humans can’t resist mystery. “You won’t believe what was found on your account” drives clicks.