What is an SBOM, exactly? A Complete Guide

An sbom meaning is a formal, organized document that details the parts of a software product as well as their connections throughout the supply chain. 

When it comes to reused code and open source, an SBOM is crucial since it outlines the packages and libraries that were utilized in your application as well as their connections to other upstream projects.

This is a comprehensive manual that lists every part that makes your new car function. 

Even if Toyota or General Motors built your car, many of its individual parts were made by subcontractors all around the world. This information is not simply interesting tidbits; it is provided in the bill of materials. 

Automobile manufacturers require a quick method to identify the location of those specific airbags in the event that a production run of airbags is recalled.

Although creating software isn’t the same as making a car, there are more similarities between the two processes than you might realize given the rise in the use of third-party open source tools to create containerized, distributed applications. SBOMs are hence becoming more typical.

Both developers and users can benefit from an SBOM by better understanding the components that went into the software they use and share. This has many important repercussions, especially in terms of security.

Why is an SBOM necessary?

Monolithic, exclusive software codebases are an outdated concept. With the aid of open source libraries, modern apps are usually built on top of extensive code reuse. 

Additionally, these applications are being gradually split up into smaller, independent functional units known as containers, which are managed by systems for container orchestration like Kubernetes and run locally or in the cloud.

In general, these innovations have helped software development by boosting developer productivity and cutting costs. 

They have, however, in many ways proven to be a security nightmare. By relying heavily on third-party code, whose inner workings they may not fully understand, developers have constructed a supply chain of software components that is every bit as complex as those used by physical manufacturers. 

Software created in this way has certain flaws that the industry is working to address because an application is only as secure as its weakest link.

The 2020s have thus far been characterized by a string of prominent software supply chain hacks. In late 2020, hackers associated with Russian intelligence were able to infiltrate a platform utilized by several security products, SolarWinds network monitoring, by adding backdoors. 

Additionally, late in 2021, a critical vulnerability in Apache Log4j, a Java library used for logging system events, was discovered. 

At first glance, this may not seem interesting, but considering that almost all Java applications use Log4j in some capacity, it makes them all vulnerable.

The significance of an SBOM 

In the security environment is shown by these security issues. Although many users may have been vaguely aware of these flaws, they were blissfully ignorant of the fact that they were using Log4j or any other SolarWinds component. 

If you had a functional SBOM, you would be able to update as necessary to be safe since you would know exactly which packages you had distributed and, more crucially, what version of those packages you had done so.

SBOMs are not limited to security

For instance, they can help software developers manage the open source licensing for the various parts of their products, which is essential if you want to share your work.

Software executive order and bill of materials

Because multiple federal agencies had used the impacted component, the SolarWinds hack in particular alarmed the US government. 

So, SBOM principles were incorporated in a significant cybersecurity executive order that was published in May. 

The Commerce Department was expressly tasked with creating a baseline of fundamental SBOM components that would later become a prerequisite for any vendor doing business with the federal government.

Even though the order only affects people who have direct connections to the federal government, it will still have an impact because of how big the US government is and how many businesses are eager to do business with it. 

After all, products that are sold to the government—which now come with an SBOM outlining their components—are also sold to other businesses and organizations. 

Many software providers believe that, despite the government pushing them in this direction, their clients in the private sector will also see SBOMs as a value-add.

Furthermore, a supply chain in and of itself is created through government contracting. 

“There are only so many organizations that conduct direct business with the federal government, and they’re definitely going to be directly impacted.” 

What details ought to go into an SBOM?

The National Telecommunications and Information Administration (NTIA) responded to the executive order by releasing “The Minimum Elements For a Software Bill of Materials” in July 2021, defining the requirements that an SBOM must achieve in order to be accepted by the federal government. 

Again, it was expected that this document would become the de facto standard for SBOMs throughout the industry because government contracting plays such a significant part in the economy. The NTIA mandated the following seven data fields for every SBOM:

• A component’s creator, definer, and identifier is identified by their name.
• Name supplied to a piece of software by its original provider, or component name.
• The version of the component: a software change from a previously identified version and the identify of the supplier.
• Additional unique identifiers: Additional IDs that can be used to locate a component or as a look-up key in pertinent databases. This could be a designation from the CPE Dictionary maintained by NIST, for instance.
• Dependency relationship: a connection whereby program Y incorporates upstream component X. In the case of open source projects, this is especially true.
• The organization that produces the SBOM data for this component is the SBOM data generator.
• Timestamp: A statement of when the SBOM data assembly was finished, including the date and time.

Additionally, SBOMs must adhere to the following standards:

• To be machine-readable, the SBOM must be in one of three standardized formats: SPDX, CycloneDX, or SWID tags.
• To keep them up to date, a new SBOM needs to be created for every new software release.
• In addition to listing dependent ties, the SBOM must also describe any situations in which such links are expected to occur but are unknown to the organization creating the SBOM.

Creating an SBOM

You might be hesitant to create an SBOM after reading this article. After all, it must be difficult to manually find all those decencies. Fortunately, you wouldn’t be required to do that. 

Typically, software composition analysis (SCA) systems generate SBOMs automatically. In DevSecOps pipelines, SCA tools are often used and frequently perform tasks other than SBOM development.