Stephanie Domas
on 24 March 2025
What is Application Security (AppSec)?
The cybersecurity world has changed. Thanks to spreading risk of cyber attacks, malware, ransomware, and the intensifying pressure of new cybersecurity regulations and sky-high penalties for leaks and breaches, robust Application Security (AppSec) is non-negotiable.
In this blog, you’ll learn how you can meet these challenges head on, and secure your operations and systems by focusing on the most fundamental aspects of your security posture. I’ll walk you through AppSec and its benefits, examine how organizations should approach AppSec design and implementation, and give you some advice and AppSec best practices from our team to help with securing your operations.
What is AppSec?
Application security (or AppSec, for short) is a broad term that refers to all of the tools, actions, and processes that an organization uses to protect its applications against vulnerabilities across the entirety of their life cycles. Application security has one objective: to find weaknesses in your applications and systems that could be abused by malicious actors to gain unauthorized access, misuse the application, or make harmful modifications, and fix them before they become a problem.
Application Security isn’t just one thing you do to secure your systems and applications. It’s everything – from early design, to your team processes, to the tools and networks you use, to the final deployment, and long term support of your products. AppSec is about doing everything you can to find vulnerabilities across your apps, organization, and processes as a whole, and improving them before they become a really big problem.
AppSec is not one single tool or technology or action. Rather, the concept covers a wide swathe of software engineering activities from development to deployment that improve an application’s overall security posture.
What are the benefits of Application Security?
Good AppSec brings a number of benefits to the organizations that use it, including more secure systems and applications, greater user trust, fewer fines and cyberincidents, and uninterrupted regulatory compliance.
In general, AppSec plays a vital role in:
- Ensuring that code is authentic and remains free of harmful modifications
- Reducing the CVE footprint of your applications
- Protecting sensitive data
- Blocking unauthorized access to applications, systems, or databases
- Stopping malicious actors, malware, data leaks, and other cyber incidents
- Ensuring regulatory compliance
- Minimizing business disruption
- Preventing security breaches and cyber incidents
- Avoiding financial, reputational, and brand damages from cyber incidents
How do you do Application Security right?
As AppSec is a broad, organization-wide practice that touches on every part of the development lifecycle, it’s important to ensure your AppSec efforts include every stage, layer, process, and tool in your organizational pipeline.
Security starts long before a single line of code is written. The vast majority of pitfalls in application security can be avoided with proper review of your chosen technologies and architecture, a thorough vulnerability assessment, and risk analysis.
You want to ensure that you’re making solid, sustainable decisions that will support your cybersecurity efforts in the long term. For example, Ubuntu is an extremely popular choice of platform for developers not just because it’s open source, but because it offers a stable, supported, and reliable foundation for meeting the inevitable challenges that arise as software grows and becomes more complex. You should treat your security design philosophy in the same way: pick something you can depend on as a ladder to future success.
Good AppSec goes hand in hand with vulnerability management (you can learn about vulnerability management in a blog we recently published) and vulnerability assessment (which we also recently covered in a blog on our website). You should conduct an extensive and deep review of your chosen architecture and planned application design, specifically with the goal of answering the question: “where are the most likely pathways and areas that malicious actors could use to mount an attack?”. This process will help you to triage and address your most likely and important vulnerabilities, while opening up a clearer roadmap to improve your overall application security posture.
However, great AppSec relies on the fundamentals in your application design and cybersecurity controls to implement robust security practices at every layer of your systems and organisation. Here a few things you should consider as you design your AppSec strategy:
- Implement a Zero Trust Strategy wherever possible
- Ensure that your authentication, authorization, and access control are fully secure (and that you have control over your credentials)
- Use Secure by Default configurations
- Minimize your attack surface – if your device or organization isn’t actively using it a port, component, package, etc, then disable it by default until it’s needed
- Ensure proper use of cryptography to guarantee that data is protected at rest and in transfer
- Encrypt all sensitive data, and avoid plaintext or cleartext data
- Validate all input and handle all exceptions
- Minimize the access permissions of apps and systems, and design your baseline to stop server-side request forgery from Day Zero
- Institute regular developer training and upskilling in security essentials, so that everyone building your apps and systems is aware of common vulnerabilities and can avoid them
You can read more about my recommendations for Application Security best practices in my dedicated, in-depth article on the subject. It covers these basics in far more detail.
There are many ways you can approach and deliver these security fundamentals, but whichever route you choose your focus should be on building a multilayered defense against attacks across attack vectors. I strongly advise that you think outside of the systems-hardening box. Remember that AppSec is holistic; you also want to closely examine cybersecurity risks that lie beyond the traditional landscape of software, hardware, and networks. This could be anything from how you hire and vet employees, to how you manage access to the building, to how your internal communications happen, both inside and outside of the workplace.
If you’re looking for a guide to what that looks like, I highly recommend reading our latest white paper on building in-depth, multilayered security.
There’s no need to do it all yourself
Every organization needs a security team, but that doesn’t mean you have to build everything yourself from scratch. There are a great number of automated tools, dedicated platforms, specialized applications, and service providers who can roll out everything you need for a secure baseline – whether it’s hands-free patching, around-the-clock monitoring and event alerts, or automated DAST/SAST tools that allow you to test your products extensively.
Take Ubuntu Pro as an example. It takes much of the manual busywork and admin out of ongoing vulnerability management, by opening up restartless and automated patching, and access to a library of over 36,000 trusted packages for the most common toolchains and applications. By using it, you take care of patching efforts for your OS and apps – no taxing, manual management needed – and you also benefit from Canonical’s 20 years of open source security expertise
If you’re looking for more help on managing vulnerabilities, securing your organization and assets, or designing your AppSec strategy, you should check out our security, or get in contact with our security team.
In conclusion, AppSec’s holistic approach shares the increasingly popular cybersecurity philosophy that security is in everything we do and everyone’s responsibility. With growing threats, brand new vulnerabilities, unforeseen attack vectors, and a rising tide of cybersecurity regulation across the world – not to mention the staggering penalties that go with them – good AppSec is a non-negotiable. Now more than ever, you should be examining your processes, designing around a refined set of cybersecurity foundational principles, and consuming packages from a trusted software supply chain.
Learn more about how you can take the manual effort and time out of much of your Application Security strategy by visiting ubuntu.com/pro
