Have you ever thought about how applications are built? They rely on various components, such as third-party libraries, frameworks, and other tools, to fast-track development and add functionalities.
For example, if you need to send HTTP requests, you’re most likely to use the requests library in Python. To build a dynamic frontend, you might use tools like React, Angular, or Vue.js.
However, what if any of these components are outdated or vulnerable? The truth is that every package, library, or framework can be a potential entry point for attackers. A single unpatched vulnerability can jeopardize the security of an entire application.
This is the essence of OWASP A06:2021– Vulnerable and Outdated Components risks. You need to be concerned not only about the security of the code you write but also the code you inherit.
This blog explores the business risks associated with vulnerable and outdated components, real-world attack scenarios, and best practices for prevention and mitigation.
Vulnerable and outdated components are just one of many risks outlined in the OWASP Top 10. For a complete picture of how these and other vulnerabilities affect web applications, check out our detailed guide on the Top 10 OWASP security risks.
What Are Vulnerable and Outdated Components?
Vulnerable and outdated components include third-party libraries, frameworks, operating systems, plugins, or any module that are no longer useful, not properly maintained, or contain vulnerabilities.
Since these components are not actively maintained by developers, fixing their bugs or vulnerabilities can be a challenging task. Furthermore, their presence complicates product maintenance, which indirectly impacts security.
For example, an application uses an outdated logging library. If this library has a known vulnerability (such as permitting unauthorized access to private logs), the entire application becomes vulnerable to attacks. If the library is incompatible with or lacks support for newer systems, it can further exacerbate the risks.
Causes of Vulnerable and Outdated Components Vulnerabilities
Understanding the root causes of vulnerable and outdated components risks is essential. Below, we have presented a few reasons:
Lack of component version documentation
Teams need a clear record of which component versions are running in the system, and these should be properly documented. Because of this lack of oversight, such outdated or insecure components can slip in the system. When you don’t know which version is running, you cannot patch.
Use of unsupported and outdated software
Unsupported and outdated components like operating systems, web/application servers, database management systems (DBMS), applications, APIs, runtime environments, and libraries, create openings for attackers unknowingly by expanding the potential attack surface.
Infrequent vulnerability scanning
If security teams fail to conduct regular vulnerability scans to identify and fix outdated components, they leave the door open for threat actors for exploitation.
Delayed or infrequent patching
Skipping regular patching of underlying platforms, frameworks, and dependencies leaves the system exposed to attackers. This usually occurs in environments where stringent procedures for software patching are not in place.
Over a period, teams start treating patching as a routine activity rather than a critical task. This mindset is not good for security and may invite trouble.
Compatibility testing omission
Inadequate compatibility testing of patched, upgraded, or updated libraries can lead to unexpected issues, such as system instability or functional failures. Worse, it may open new vulnerabilities, or cause integration problems. Regular compatibility testing helps catch such issues early.
Key Business Risks of Vulnerability and Outdated Components
Ignoring vulnerable and outdated components can significantly impact an organization’s security posture. Threat actors can exploit inherent security weaknesses in these components to launch attacks such as SQL injection and cross-site scripting (XSS).
Such vulnerabilities can lead to sensitive data breaches and operational disruptions. Using components from unreliable sources or those not actively maintained poses additional risks, as these components do not receive timely patches for newly identified vulnerabilities. Ultimately, this compromises the confidentiality and integrity of critical systems and data.
OWASP A06: A Real-World Attack Scenario
Outdated or vulnerable components are low-hanging fruit for attackers. Attackers may exploit known flaws in these components to launch attacks such as SQL injection or cross-site scripting (XSS).
These weaknesses can lead to data leaks and disrupt normal operations. Relying on tools or software from unreliable sources — or those that no longer receive updates — increases the risk, as they often miss critical security patches. Left unchecked, these gaps leave your systems sensitive and exposed to attacks. Here is a list of associated CWEs with A06:
- CWE-1104: Use of Unmaintained Third Party Components
- CWE-937: Use of Components with Known Vulnerabilities
Best Practices for Prevention of Vulnerable And Outdated Components Risks
Here is a list of best practices for reducing the risk from vulnerable and outdated components:
1. Keep API frameworks and libraries updated
Always use the latest stable versions of API frameworks like:
- Node.js (Express, Fastify)
- Python (Flask, Django, FastAPI)
- Java (Spring Boot, Jakarta EE)
- NET (ASP.NET Core)
- Ruby (Rails, Sinatra)
2. Remove unused components
Regularly conduct security audits to identify all unused dependencies, unnecessary features, components, files, and third-party libraries from the system environment. This helps minimize the attack surface and reduces the chances of potential vulnerability exploitation.
- Use tools like a Software Bill of Materials (SBOM) to track component versions and known vulnerabilities.
- Integrate security tools such as Snyk into your CI/CD pipeline to detect and patch issues early.
3. Properly document inventory components
- Maintain separate inventories for client-side and server-side components, including all frameworks and libraries.
- Track vulnerabilities by regularly checking trusted sources like the CVE database and NVD.
- Use SCA tools to automate the discovery and monitoring of third-party and open-source components.
- Stay informed by subscribing to vulnerability alerts and security advisories relevant to the tools and libraries your systems rely on.
4. Use trusted repositories
- Always use components from official and trusted repositories, such as Ubuntu, Debian, Red Hat, CentOS, Rocky Linux, or Arch Linux, REMI, PyPI (Python), npm (Node.js), or RubyGems.
- Prefer signed packages to minimize the chance of malicious components.
5. Regularly monitor unmaintained components
- Set up a process to regularly monitor and track unmaintained third-party libraries and components.
- Avoid creating security patches for older versions of components.
- If patching is not possible, consider deploying virtual patches to monitor, detect, or protect against identified vulnerabilities.
6. Develop a patch management process
- Establish a formal patch management policy that defines the organization’s principles, scope, and responsibilities regarding software patching.
- Create comprehensive documentation detailing patching procedures, techniques, schedules, and clearly assigned roles and responsibilities.
- Classify assets based on their risk level and business criticality to prioritize patching efforts accordingly.
- Thoroughly test patches in a controlled sandbox environment to identify potential compatibility or stability issues before deployment.
- Perform full system backups prior to applying any patches, ensuring recovery options in case of failure.
- Deploy patches in stages, starting with non-critical or low-risk systems to monitor for unforeseen issues before broader rollout.
7. Follow compatibility testing
- Only use the components that are being actively maintained by the developers community.
- Keep a tab on regular advisories released by component developers.
8. Secure API authentication & authorization
- Use OAuth 2.0, OpenID Connect, or API keys with secure implementation practices to manage access to APIs and services.
- Implement JWTs (JSON Web Tokens) with appropriate expiration times and secure signing algorithms (e.g., RS256) to prevent token misuse.
- Deploy RBAC (Role-Based Access Control) or ABAC (Attribute-Based Access Control) to enforce fine-grained authorization based on user roles or attributes.
9. Use secure dependency management
- Use reliable package managers like npm, pip, Maven, or NuGet to handle your dependencies — they help you stay organized and reduce risk.
- Use automated tools like Dependabot or Snyk to catch outdated or vulnerable packages before they become a problem.
10. Enforce Secure Communications
- Use HTTPS with TLS 1.2 or higher for all API communications.
- Implement certificate pinning to prevent man-in-the-middle (MITM) attacks.
- Set strict Cross-Origin Resource Sharing (CORS) policies to restrict API access to trusted domains.
Mitigation Techniques for Vulnerable And Outdated Components
Outdated or unused components create blind spots for attackers to exploit. Below, we have presented some mitigation techniques:
1. Conduct a security audit
Post-incident audits help uncover which legacy features or dependencies might be exposing you to risk. For example, reviewing API endpoints, middleware, or third-party libraries can reveal which specific components contributed to a breach. If an old OAuth 2.0 library or a vulnerable API gateway turns out to be the weak link, upgrading or replacing it quickly is key to closing that gap.
2. Apply the principle of least privilege
The Principle of Least Privilege (PoLP) limits damage by restricting access to only what is necessary. This approach can contain the impact of an attack to a limited scope.
Say an attacker exploits a flaw in an outdated library. With PoLP in place, compromised components have minimal access and permissions, restricting lateral movement or privilege escalation.
One way to apply PoLP is by restricting access to API endpoints and carefully scoping API key permissions. Only authorized clients or roles should be able to reach sensitive endpoints.
If a vulnerability in an API authentication library is exploited, PoLP ensures the compromised component can only access non-sensitive data, preventing broader system compromise.
3. Implement web application firewall (WAF)
A WAF can act as a temporary shield when a patch isn’t in place yet. It helps spot and block attempts to exploit known flaws in outdated components. For example, if there’s a vulnerability in an old REST API framework, a WAF can catch and stop malicious traffic targeting that weakness, providing your team with a buffer until the fix is rolled out.
4. Monitor third-party APIs
API gateways enforce security policies, rate limiting, and API authentication, acting as a barrier between the client and the backend APIs. This ensures outdated or vulnerable components are not directly exposed to the public.
For example, use an API gateway like Kong or AWS API Gateway to monitor API traffic and block suspicious or malicious requests targeting outdated components.
5. Secure third-party integrations
Third-party APIs can be a hidden security risk if they’re not properly vetted and maintained. Always check that they use secure authentication (like OAuth 2.0), encrypt data in transit, and include rate limiting to prevent abuse.
For critical tasks like payment processing, for example, using Stripe, use official SDKs and keep them updated. Outdated versions can carry known vulnerabilities, and that’s not a risk worth taking.
Conclusion
Vulnerable and outdated components risks might not seem urgent at first, but they’re one of the most common ways attackers break into systems. To reduce risk, it’s crucial to establish a process that routinely identifies and updates these components.
Want expert help securing your software stack? Our penetration testing services can uncover hidden vulnerabilities and ensure your systems stay protected. Get in touch today to strengthen your component security strategy.
Reference resources:
Virtual Patching Best Practices | OWASP Foundation
CWE – CWE-1104: Use of Unmaintained Third Party Components (4.17)
