Outdated software refers to the use of older versions of software components or dependencies in open source projects while newer, updated versions are available. This lag in updates can result in several issues, including unpatched security vulnerabilities, compatibility problems, and reduced functionality. Over time, it may become increasingly difficult to apply updates in response to urgent vulnerabilities or to take advantage of new features, as major version updates may involve breaking changes.

For example, using an outdated library version, like a deprecated Apache Tomcat branch, can mean missed security patches. Additionally, as components age, they reach EOL, meaning that their maintainers may stop providing updates altogether, further increasing the risk.

In this lesso, you will learn how outdated software can introduce risks to open source projects, how to identify and mitigate those risks, and how to keep dependencies up to date. Through an interactive example, we’ll examine a case where reliance on outdated software caused a serious security breach.

Anna is the lead developer for an open source project called "PhotoShare." The project uses a widely popular image processing library, FastImages, for resizing and filtering photos. Unbeknownst to Anna, her team is still using version 1.4 of FastImages, while the current version is 2.3. Anna assumes the library is secure and hasn't considered updating it since its integration two years ago.

One day, a security researcher contacts Anna with an alarming report: a critical vulnerability was found in FastImages 1.4 that allows remote code execution. A malicious actor could exploit this flaw to take over servers running the library. Worse, the vulnerability had been patched in version 2.0, released over a year ago.

She realizes that skipping regular updates has left her project vulnerable. She alerts the security team who investigates how the vulnerability could be exploited. To test that the issue can be exploited, the security team sends a specially crafted image file to the PhotoShare server. The upload request looks like this:

Let's breakdown this payload line-by-line to see how it works.

To recap, the exploit payload is hidden inside a seemingly normal image upload. If the server processes .mvg files insecurely with ImageMagick, it may execute the injected command. The attacker's server at http://attacker.xy (obviously not a real attack server!) would receive the contents of /etc/passwd.

Now let's see how we can mitigate this!

Let’s examine how the outdated library (FastImages version 1.4) caused a vulnerability in the PhotoShare application. The vulnerable library failed to properly sanitize metadata in uploaded files, allowing crafted payloads to execute malicious commands.

In the code snippet below, the fast-images library processes an uploaded file. The library is responsible for parsing and manipulating image files, including handling embedded metadata. However, in the outdated version, metadata fields are passed to a shell execution function without sanitization or validation. If the uploaded file contains malicious metadata, such as a crafted url() value in an MVG file, the library will execute the command during parsing. This allows attackers to run arbitrary commands on the server, such as exfiltrating sensitive data or installing malware.

The code snippet below uses the process_image function from the outdated FastImages library to handle image uploads. The library parses the image file, including its metadata, to generate thumbnails and other image modifications. However, the outdated version of the library interprets metadata fields as shell commands in certain formats, such as MVG. For example, a fill property in the metadata might contain a crafted command that is executed during processing. This vulnerability could be exploited to gain unauthorized access to the server or execute arbitrary code, such as downloading malicious files or stealing sensitive information.

In the code snippet below, the FastImages::process() function is used to process an uploaded image file. The outdated version of the library has a critical flaw in its handling of metadata in certain file formats. During processing, metadata fields are passed to a shell execution function without proper sanitization or escaping. If an attacker uploads a malicious file containing commands in the metadata, those commands are executed as part of the file parsing process. This could allow an attacker to perform operations like creating backdoors, accessing sensitive server files, or launching further attacks.

The code snippet below uses the FastImageProcessor.Process method to handle image uploads. The outdated version of the library processes metadata fields directly, without ensuring they are safe for execution. This becomes particularly dangerous with certain file formats like MVG, where metadata can contain external command invocations. The library executes the metadata as part of rendering the image, allowing attackers to execute shell commands. This can result in the compromise of server data, installation of malware, or unauthorized network requests.

In the code snippet below, the fastimages.Process function processes uploaded image files by parsing their metadata and performing transformations. The outdated version of the library incorrectly assumes that all metadata is benign and directly interprets certain fields, such as URLs or PostScript commands. An attacker can upload a file with malicious metadata to execute commands on the server during processing. This could be used to retrieve sensitive information, escalate privileges, or launch additional attacks against the system.

The code snippet below uses the FastImages.process method to handle image files uploaded to the application. The outdated version of the library fails to properly validate metadata fields within certain image formats. For example, the MVG file format supports commands within the fill or stroke properties, which the library processes without escaping or validation. An attacker can exploit this by embedding a malicious command in the metadata, leading to the execution of arbitrary shell commands on the server, which could result in data exfiltration or system compromise.

In the code snippet below, the FastImages::Process function processes an uploaded file. The outdated version of the library processes image metadata as part of rendering or conversion operations. If the metadata contains malicious commands, such as a curl command embedded in an MVG file, the library executes these commands without validation. This creates an RCE vulnerability, allowing an attacker to control the server’s behavior, exfiltrate sensitive files, or install malicious software. The lack of proper input validation and escaping in the outdated library makes it susceptible to such attacks.

When a dependency is not updated, it remains vulnerable to any issues discovered in its outdated version. These vulnerabilities often become widely known over time, making them an attractive target for attackers. Exploiting these known issues can result in catastrophic consequences, such as unauthorized access to sensitive data, remote code execution (RCE), or full system compromise.

In addition to security concerns, outdated dependencies can lead to operational challenges. Compatibility issues may arise when integrating with newer systems or libraries, causing disruptions and increasing development overhead. Furthermore, as components reach their end of life (EOL) and maintainers stop providing updates, projects relying on these components may face growing technical debt and reduced maintainability.

In high-stakes environments, such as healthcare or finance, where compliance with regulatory standards is critical, outdated software can also lead to legal penalties. The combination of security, operational, and compliance risks makes keeping dependencies updated an essential practice for any open source project.

Keeping your software up to date is crucial for security, and the best way to manage dependencies is to be proactive. One of the most effective strategies is automating updates. Tools like Snyk Open Source can continuously monitor your project’s dependencies, alerting you to new releases or security issues. Some tools can even generate pull requests for updates, saving developers time and reducing the risk of human error.

It’s also important to keep a clear record of all your dependencies, including both direct and transitive ones. Make sure to track key details like version numbers, release dates, and end-of-life (EOL) status. Regularly reviewing this inventory helps identify outdated dependencies so they can be updated or replaced before they become a security risk.

Another key step is integrating security tools into your CI/CD pipeline. These tools can scan for vulnerabilities in your dependencies and alert you to critical issues right away. Using semantic versioning also helps teams understand the impact of updates—whether they introduce breaking changes or just security fixes.

Remember, maintaining security isn’t just about tools, it’s about mindset. Encourage a culture of regular maintenance by setting clear policies for dependency updates, defining SLAs for patching vulnerabilities, and scheduling regular reviews. Keeping outdated software in check is an ongoing process, but with the right habits and automation in place, it becomes much easier to manage.

Mitigated code

The mitigated snippet below processes an uploaded file using the fast-images library. The file path is passed to the fastImages.process function, which parses the file, including its metadata, and generates any necessary outputs, such as thumbnails. While the code remains almost identical to the previous vulnerable version, the difference lies in the updated fast-images library. The library now includes strict metadata validation and rejects any potentially harmful content, ensuring that malicious payloads embedded in image files cannot execute commands on the server. This change highlights that the issue is primarily operational, as it was resolved by updating the library rather than modifying the application's code.

The mitigated snippet below uses the process_image function from the FastImages library to process an uploaded image. The function parses the file and its metadata, enabling tasks like image resizing or thumbnail generation. The security flaw is addressed by updating the FastImages library to a newer version that sanitizes metadata fields and prevents command execution. The application code itself remains mostly unchanged, emphasizing that the vulnerability was a library-level issue. This scenario underscores the operational responsibility of maintaining updated dependencies to ensure application security.

In the mitigated snippet below, the FastImages::process() function processes an uploaded image file. It parses the file’s metadata and performs operations such as resizing or transformation. The vulnerability has been fixed in the updated FastImages library, which now properly validates metadata and eliminates the ability for commands to execute during processing. The application code is effectively unchanged, demonstrating that the issue was rooted in the library rather than the implementation. As such, this scenario illustrates the operational importance of keeping third-party dependencies updated.

The mitigated snippet below uses the FastImageProcessor.Process method to process uploaded files. The method parses the file’s metadata and performs image-related operations. While the code itself is almost identical to the previous version, the security improvements come from the updated library. The FastImageProcessor library now validates metadata fields and prevents malicious payloads from being executed. This resolution required no changes to the developer's code, highlighting that the issue was operational in nature, stemming from an outdated dependency rather than an inherent flaw in the application's logic.

In the mitigated snippet below, the fastimages.Process function is called to process uploaded files. The function parses metadata and performs necessary transformations on the image. The updated fastimages library resolves the vulnerability by ensuring metadata fields are sanitized and rejecting harmful inputs during processing. Since the application's code remains unchanged, this example illustrates how the problem was operational rather than code-based, reinforcing the need for dependency management as part of routine maintenance.

The mitigated snippet below uses the FastImages.process method to handle uploaded image files. The method parses the file’s metadata and executes transformations as needed. The updated version of the FastImages library introduces robust metadata validation, ensuring that commands embedded in the file cannot be executed. The fact that the application code is virtually identical to the earlier vulnerable version demonstrates that this was not a development issue but an operational one. Regular updates to dependencies would have prevented the vulnerability from being exploitable.

In the mitigated snippet below, the FastImages::Process function processes an uploaded image file, parsing its metadata and performing necessary transformations. The updated FastImages library resolves the security issue by validating metadata and removing the ability to execute external commands during processing. Since the code itself does not require any significant changes, this highlights the operational nature of the vulnerability. Maintaining updated libraries is a critical aspect of securing applications, as outdated dependencies are often the root cause of such issues.

To further enhance your knowledge about outdated software and dependency management, here are some valuable resources:

• Snyk Open Source Security Management – Discover how to integrate automated vulnerability detection and remediation into your development workflow.
• Semantic Versioning – Understand the principles of semantic versioning to make informed decisions about updates and assess the impact of new dependency versions.
• NVD Vulnerability Database – Stay informed about known vulnerabilities by searching through the National Vulnerability Database.

By exploring these resources, you can deepen your understanding of managing dependencies and ensure your software remains secure, stable, and up to date.