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Dropper
What it is A dropper is a sneaky Trojan that looks harmless, gets past first checks, and then installs other malware - ransomware, stealers, spyware. Some droppers stick around (persistent) to keep the door open after a reboot; others do the job once ...
Downloader Trojan
What it is A downloader trojan is a malware dropper: it sneaks in looking harmless, then quietly downloads and runs more malware - ransomware, stealers, spyware, you name it. Think of it as the first domino in an infection chain. Learn more in our ...
Domain Spoofing
What it is Domain spoofing is when attackers pretend to be a trusted website or sender by using a look-alike address - think paypaI.com (with a capital “I”), or emails that seem to come from your bank. The goal is to trick you into entering ...
DNS-based Blackhole List (DNSBL / RBL)
What it is A DNS-based Blackhole List is a reputation list you can query via DNS to spot known bad senders - IP addresses or domains tied to spam, malware, or abuse. Mail and security gateways check these lists in real time to block or flag risky ...
DNS Tunneling
What it is DNS tunneling turns the internet’s phone book (DNS) into a secret tunnel for data. Because DNS lookups are trusted and often allowed out of networks, attackers hide commands or stolen info inside DNS requests and replies to sneak past ...
DNS Rebinding Attack
What it is DNS rebinding is a web trick that makes your browser talk to places it normally shouldn’t - like your home router, NAS, or an internal app - by rapidly changing a site’s DNS answer. You think you’re visiting a normal page; your browser is ...
DNS Hijacking
What it is DNS hijacking is when someone tampers with the internet’s phone book (DNS) so your browser goes to the wrong site—often a fake login page or a malware download—even though you typed the right address. Get the full rundown in our DNS ...
DNS Firewall
Why it matters Most attacks start with a click or a background connection. Stopping bad domains at the DNS layer cuts off malware downloads, phishing pages, and command-and-control beacons without slowing users or changing their workflow. How it ...
DNS Filtering
Why it matters Most threats start with a click. Stopping connections at the DNS layer cuts off malware downloads, command-and-control beacons, and fake login pages -without slowing users or breaking trusted sites. How it works Your device asks DNS ...
DNS Blocking
What it is DNS blocking is a simple filter for where devices are allowed to go on the internet. When a user tries to visit a domain on the block list, the DNS resolver refuses or sends them nowhere - so risky or unwanted sites never load. How it ...
Djvu (STOP) Ransomware
What it is Djvu - also called STOP - is ransomware that breaks into Windows PCs, encrypts your files, and adds new extensions (often .djvu, .stop, or a variant). A note then demands payment in crypto to unlock them. For details and removal tips, see ...
Digital Footprint
What it is Your digital footprint is the trail you leave online—searches, posts, likes, app logins, purchases, even where your phone has been. Some of it you publish on purpose (profiles, comments). Some of it is collected quietly (cookies, ad ...
Defense in Depth (DiD)
What it is Defense in Depth is the “many locks, many alarms” approach to security. Instead of betting on one tool, you stack multiple layers - people, process, and technology - so if one layer slips, the next one catches the attack. Why it matters ...
Deception Technology
What it is Deception technology plants convincing decoys—fake servers, files, credentials, and “honey” accounts—so attackers probe the traps instead of your real systems. When they bite, you get high-fidelity alerts and a clear view of their tools ...
DDoS (Distributed Denial of Service)
What it is A DDoS attack is a traffic jam on purpose. Thousands of hacked devices (a botnet) or misused services flood your site, app, or API with requests so real users can’t get through. Outages can last minutes—or much longer without a plan. How ...
Data Loss
What it is Data loss is when important files—photos, projects, invoices—disappear or become unreadable. It happens for lots of boring-but-real reasons: accidental deletes, failing drives, malware, spilled coffee, power cuts, or disasters. Common ...
Data Exfiltration
What it is Data exfiltration is the unauthorized transfer of your data out of your device or network—quietly slipping customer records, passwords, designs, or finances to an attacker. It’s the punchline of many breaches: get in, get data out, cash ...
Data Execution Prevention
What it is Data Execution Prevention (DEP) is a Windows safety net that stops code from running in places it shouldn’t—like the stack or heap. If malware tries to execute from those memory areas, Windows blocks it and shuts the app down instead of ...
Data Breach Prevention
Why it matters Breaches drain money, trust, and time. Strong basics turn scary “what ifs” into non-events: a phish gets ignored, a stolen password is useless, a lost laptop holds only encrypted gibberish. The short, smart checklist MFA everywhere: ...
Data Breach
What it is A data breach is when someone gets into a company’s systems without permission and steals sensitive info—customer names, emails, passwords, payment details, medical records, and more. For overview: see our data breach guide How it happens ...
Datastore
What it is A datastore is a place where apps keep their information - like a digital filing cabinet. It can be a spreadsheet-style database (rows and columns), a NoSQL store for flexible records, a blob/object store for files and images, or even a ...
Darknet
What it is The darknet is a part of the internet that runs on private, encrypted networks where visitors and website owners can stay anonymous. You need special software (like Tor) to reach these sites. Not everything there is illegal, but the ...
DanaBot
What it is DanaBot is a banking trojan for Windows that sneaks onto a PC, watches your web sessions, and tries to steal logins and payment data—especially for online banking. It’s modular, so criminals can bolt on extras like spam sending or ...