Developers are using Python more commonly than ever. Research shows that 51% of developers rely on Python for web development, automation, data analysis, and artificial intelligence projects.
Its clean syntax, huge community, and wealth of libraries make it one of the most beginner-friendly and business-friendly programming languages today.
But as Python use continues to grow, so does the importance of securing the applications built with it. Cybercriminals are becoming more sophisticated, and they target vulnerabilities wherever they can find them.
Just recently, ShinyHunters, a black-hat criminal hacker and extortion group, hacked Google data through Salesforce. Google’s August update shows that the group (UNC6040) is now using clever custom Python scripts alongside privacy tools to launch targeted web application attacks.
That’s enough to say why you must bake security into every stage of web application development. Here, we’ll share some best practices that can help you fortify Python web applications against cyberthreats.
Python Web Applications Against Cyberthreats
Table of Contents
#1 Use a Secure Python Web Framework
The framework you choose determines how well defense is built in automatically. Some popular frameworks are champions of security right out of the box. Others require manual assembly of protection layers.
Django is commonly known as a “batteries included” framework. This means many necessary security defenses are ready for immediate use. No wonder 12% of developers use it.
Django’s ORM (Object-Relational Mapper), for instance, automatically escapes SQL queries, making it very hard to accidentally open the door to SQL injection attacks. Django also includes built-in middleware to protect against CSRF attacks.
Flask and FastAPI are smaller, more flexible frameworks that give you more control. But with that freedom comes responsibility. They don’t automatically include as many built-in security features as Django, so you’ll need to be proactive about adding them.
You must manually configure critical parameters in Flask. Setting the SECRET_KEY is mandatory for session security and signing tokens. To protect against denial of service (DoS) attacks, configure input limits. These limits include MAX_CONTENT_LENGTH and MAX_FORM_MEMORY_SIZE.
For fundamental features like cross-site request forgery (CSRF) protection, Flask needs external extensions. A common option is Flask-WTF. You must register the CSRFProtect extension globally.
#2 Never Trust User Input
User input is the primary point of entry for security vulnerabilities. Validation, or checking input against set rules, is the first line of defense. Simple Python helpers like str.isalnum() can check for letters and numbers.
After validation comes sanitization. It removes or encodes suspicious characters to prevent malicious scripts from executing in your code.
A major threat here is SQL Injection (SQLi), where attackers insert harmful commands into your database queries. To stop SQLi, always use parameterized queries, which clearly separate commands from data.
This step becomes even more important for businesses that gather private data of clients. For example, law firms often collect sensitive client information through chatbots or online forms. Cybercriminals can target them to access confidential information.
Consider the example of a personal injury law firm working on a Bard Power Port lawsuit. According to TorHoerman Law, the lawsuit centers on claims that Bard Access Systems failed to create a safe vascular access device. Since health data is at risk, the stakes are bigger.
When a client enters their case details into a law firm’s chatbot to check potential Bard Power Port lawsuit settlement amounts, hackers get access to private information. Without proper input validation, an attacker could exploit that form to inject malicious code, steal client data, or redirect users to fake pages. But that won’t happen if you validate and sanitize user input.
#3 Use Security Headers
Security headers are an easy but often overlooked way to protect your web app. These are basic instructions you send to the user’s browser. They tell the browser exactly how it should treat your website. These headers offer valuable protection even if your Python code has a tiny flaw.
HTTP Strict Transport Security (HSTS) is a must-have header. After a user connects securely once, HSTS ensures the browser never attempts to use unencrypted HTTP again. This prevents protocol downgrade attacks where hackers try to force a less secure connection.
Clickjacking attempts to trick users into clicking invisible items. Attackers do this by loading your site inside a transparent <iframe> on their own site.
The X-Frame-Options (XFO) header is the standard defense against this. It tells the browser whether your page can be rendered inside a frame.
Using DENY prevents framing completely. SAMEORIGIN only allows framing by pages on your own domain. You must use both XFO and the newer Content Security Policy (CSP) directive for defense-in-depth against framing.
Content Security Policy (CSP) is your strongest firewall against cross-site scripting, or XSS. CSP severely restricts which resources the browser is allowed to load. It specifies the exact, trusted domains for scripts and images.
Integrating Security into the DevOps Flow
You don’t have to become a cyber superhero to secure Python web applications. A few good habits from the get-go can fortify the apps against cyberthreats.
Just a heads up: Security isn’t a ‘set it and forget it’ thing. Review the app regularly, test for vulnerabilities, and keep learning about new threats and best practices. Rest assured that it will be much harder for attackers to exploit the applications you create.
Also Read: Tips to Fortify Python Web Applications Against Cyberthreats
