CyberSecurity & DevSecOps Expert: Develop, PenTest, and Deploy Secure Applications

**Theoretical Recap** In the previous workshop, you built a Python script that executes the `ping` command using the `subprocess` library and saves the output to a file. That script worked, but it used a hardcoded, default number of packets — meaning...

**Theoretical Recap** The `subprocess` module is Python's standard way to launch system commands from a script. It replaces the older `os.system()` approach and gives you fine-grained control over the process: you can capture stdout and stderr, pass ...

In the previous activities, you learned how to read files, handle exceptions, organize your code into modules, and document your work. Now you will take a new step: interacting with the operating system directly from Python. This is a fundamental ski...

When you write Python scripts for security automation — whether that means parsing log files, detecting anomalies, or automating vulnerability checks — your code does not live in a vacuum. Other people will read it, modify it, and build on it. You yo...

**Theoretical Recap** A module in Python is simply a .py file containing functions, variables, or classes that you can reuse across multiple scripts by importing it. When you write import utils or from utils import my_function, Python looks for a fil...

When you write Python scripts to automate security tasks — scanning a network, parsing log files, or detecting suspicious patterns — you quickly realize that reinventing every function from scratch is neither efficient nor realistic. Python solves th...

When you write Python scripts for security automation — whether to parse log files, detect anomalies, or interact with network services — bugs are inevitable. Knowing how to debug efficiently is not optional: it is a core professional skill. This cha...

**Theoretical Recap** Exception handling in Python is a fundamental mechanism that allows your program to react gracefully when something unexpected happens at runtime, instead of crashing abruptly. The core syntax revolves around the try/except bloc...

When writing Python scripts for security automation, you will inevitably encounter situations where your code tries to do something that fails at runtime: opening a file that does not exist, connecting to a server that is offline, reading malformed d...

**Theoretical Recap** In Python, reading a text file relies on the built-in `open()` function, which returns a file object. The standard pattern is to use `open()` in combination with a `with` block, which ensures the file is properly closed after re...

In the context of security automation, reading files is one of the most fundamental and frequently used operations. Whether you are parsing log files to detect suspicious activity, reading a list of IP addresses to scan, loading a wordlist for a brut...

**Theoretical Recap** An interactive menu in Python is a control structure that repeatedly presents options to the user, reads their input, and dispatches execution to the appropriate function based on that choice. It combines three concepts you have...

**Theoretical Recap** A function in Python is a reusable, named block of code that performs a specific task. You define it once using the `def` keyword, and call it as many times as needed throughout your script. Functions can accept parameters (inpu...

Functions are one of the most fundamental building blocks in Python programming. They allow you to group a set of instructions under a single name, and then reuse that group of instructions as many times as needed throughout your program. If you have...

**Theoretical Recap** A scheduled task is a program or script that runs automatically at defined intervals or after a set delay, without human intervention. In cybersecurity and DevSecOps, scheduled tasks are everywhere: log rotation, automated vulne...

**Theoretical Recap** Python scripts become truly useful when they can adapt their behavior based on external input rather than running the same fixed logic every time. Command-line arguments, accessed via the `sys.argv` list, allow a script to recei...

Up to this point in the course, you have been writing Python code using variables, conditions, and loops. You have tested your scripts interactively or by running simple files. Now it is time to take a step further: writing Python scripts that can be...

**Theoretical Recap** A `while` loop repeats a block of code as long as a given condition remains True. Unlike a `for` loop — which iterates over a known sequence — a `while` loop is ideal when you do not know in advance how many iterations are neede...

**Theoretical Recap** A `for` loop in Python iterates over a sequence — a range of numbers, a list, or any iterable object — and executes a block of code for each element. The built-in `range()` function is essential here: `range(start, stop, step)` ...

In the previous activities, you learned how to declare variables, convert types, and make decisions using if/else conditions. You now know how to write a Python script that reacts differently depending on a value. But what happens when you need to re...

**Theoretical Recap** In networking, ports are numerical identifiers ranging from 0 to 65535 that allow operating systems to route incoming and outgoing traffic to the correct process or service. Ports below 1024 are called 'well-known' or 'reserved'...

In the previous activities, you learned how to declare variables, assign values to them, and perform basic type conversions. You now have the building blocks to store information in your Python scripts. However, a script that always executes the same...

**Theoretical Recap** In Python, every value has a type: int (integer), float (decimal number), str (string of characters), bool (True/False). In real-world security scripting, data rarely arrives in the format you need. A port number read from a fil...

**Theoretical Recap** In Python, a variable is a named container that stores a value in memory. Unlike languages such as C or Java, Python is dynamically typed: you do not need to explicitly declare the type of a variable before assigning a value to ...

Variables and data types are the absolute foundation of any Python program. Before writing any security automation script — whether to scan a network, parse HTTP responses, or manipulate file contents — you must understand how Python stores, names, a...