All Episodes

Red thread — Building a complete threat matrix for the Blog

Identify STRIDE threats in the DFD

Data Flow Diagram (DFD) — symbols and best practices

Draw the DFD for the Blog application

STRIDE on a “create post” API endpoint

Apply STRIDE on the authentication flow

Break down the simplified Blog application into components

Why model threats? Benefits and key steps

Classify CIA impacts on Todo List assets

Actor vs Attacker — clarifying roles

Confidentiality, Integrity, Availability (CIA) — foundations

Scan /var/log/auth.log for detections

Create a restricted pentest user

Advanced user and sudoer management

Make it executable and schedule via cron

Best practices & pitfalls in scripting

Write a /etc backup script

Bash scripting: variables, loops, conditions

Third-party security updates and repositories

Install nmap and wireshark

Package management: apt, yum/dnf

Document network status

Identify open interfaces and ports

Local network tools: ip, ss, netstat

Debugging services and reading systemd logs

Start, stop, activate a service

Services with systemd: units & log

Signals and kill in practice

List and filter processes

Process management: ps, top, nice

Summary & navigation/permissions memo sheet

Special bits: setuid, setgid, sticky

Securing a shared folder

Chown and chgrp

Diagnosing common permission errors

Digital chmod 755/644

Symbolic chmod step by step

Permissions and Ownership: Introduction

Securely copy, move, and delete

File manipulation: touch, mkdir, cp, mv, rm

Linux file system hierarchy

Explore with tree

Common navigation pitfalls

navigation (cd, paths)

First steps: pwd, ls, clear

Linux terminal: key concepts

Welcome and chapter goals

Final mini-project: basic audit script (ping, nmap, headers) with report

Reinforced workshop: applying best practices to hello.py

Secure scripting best practices (rights, shebang, secrets)

Workshop: check for the presence of X-Frame-Options

Requests library: HTTP request and header analysis

Generate reports: text, CSV, and JSON

Mini-project step 1: Nmap wrapper (runtime + XML capture)

Manipulating dates and timstamps for newspapers

Introduction to sockets: scanning a port

Workshop: scan ports 20 to 25 of a local target

Workshop: extracting all IP addresses from a log

Regular expressions: extract patterns

Workshop: Port → service dictionary

Workshop: create a list of ports and go through it

Data structures, lists and dictionaries

Workshop: Setting the number of ping packets

Workshop: script that executes 'ping' and saves output

OS and subprocess libraries to launch commands

Documentation and comments: writing docstrings

Workshop: creating and importing utils.py

Modules, packages, and pips: reusing code

Debug your script: print vs pdb

Workshop: managing FileNotFoundError on the log

Exception handling: try/except

Workshop: reading a log and counting ERROR lines

Reading text files: open, read

Workshop: interactive mini-menu to choose an action

Workshop: est_pair (port) function

Define and call simple functions

Workshop: alert if a port is reserved (<1024)

Visualize a network flow with an online simulator

Topology concept, switch vs router

Associate IP addresses with equipment

Observe an ICMP packet with ping