Cyber Security 101

Every lesson in the Cyber Security 101 slide course, in full text: 3 decks, 212 slides.

• PowerShell and Linux: Getting Into FilesA beginner session built around one wall: not being able to get into specific files. The filesystem as a building, PowerShell's verb-noun naming rule and three lifeline commands, finding hidden files anywhere on a drive and reading them, pipelines and the comparison operators, the same ideas in Linux with a translation table, why case sensitivity and permissions cause most 'file not there' errors, and a six-question checklist for being stuck in a room.
• Networking From the Ground Up: Addresses, Ports, Protocols and the RoomsThe module that follows the command line in the Cyber Security 101 path, built for a beginner who can run commands but has no picture behind them. It covers the two-address system and why both are needed, the private ranges, reading slash notation and turning a prefix into a usable host count, the four-layer model, DHCP, ARP and NAT, ports with TCP against UDP and the three-way handshake, the difference between closed and filtered, DNS lookups and the records worth enumerating, what the TLS padlock does and does not prove, and the eight commands that open almost every networking room.
• Software Bugs: The Vulnerability Classes and How to Find ThemThe introduce-a-bug-then-find-it session: students plant one documented vulnerability in a small program, swap with a partner, and hunt down the partner's bug the way a reviewer does. It separates a bug from a vulnerability from an exploit, walks the main weakness classes with real code — memory-safety (buffer overflow, off-by-one, use-after-free, integer overflow), injection (SQL, command, cross-site scripting, path traversal), broken access control and logic bugs, race conditions and TOCTOU, and data-handling bugs (hardcoded secrets, weak crypto, insecure deserialization) — explains honestly how bugs get into code including the deliberate insider and supply-chain case, reframes what makes a bug subtle as a reviewer's checklist, and teaches the detection toolkit in order: static analysis and secret scanning, human review of the risky lines, adversarial and regression testing, and fuzzing, closing with a full bug-report template.