Open-Source Software Bill Of Materials Explained

A software Bill of Materials is based on the concept of a manufacturing Bill of Materials, which is an inventory of all the elements involved in a product. Manufacturers in the automotive industry, for example, keep a thorough Bill of Materials for each vehicle. The parts made by the original equipment manufacturer and parts from third-party vendors are all listed in this Bill of Materials. When a problematic item is detected, the automaker can easily determine which vehicles are affected and inform owners of the need for repair or replacement. This principle is typically applied to both open sources as well as proprietary software.

Why Software BOMs are Important

Regulatory compliance plays a key role in all major organizations, and it is no different for application development houses. The legal requirements of each open-source library and tool might be vastly different from one another. As a result, determining licensing responsibilities might be difficult without a comprehensive open-source BOM. It is therefore important to diligently itemize each license and its limitations of use. 

An additional dimension is software patching. Open-source patching isn’t as simple as using legal grounds to force a vendor to comply. The software BOM facilitates transparent version control to ensure that patches are accurately applied. 

Another reason why software BOMs are important- is bugs. Whether software bugs have been intentionally or inadvertently introduced into utilized open-source code sets, it needs to be traceable at all times. A thoroughly compiled software BOM will allow developers to trace and track down buggy libraries and components. If such code-sets are not accurately documented in the software BOM developer would not have a clue where to start looking for bugs.

Any software, whether open source or proprietary, will be released in predefined release cycles, upgrading during each interim. Without software, BOM developers might lose track of release cycles possibly resulting in unwanted technical debt, which, if caught up might see utilized functions and features being deprecated. Applying development releases of source code into a production environment is also a risk in this regard.

A software BOM must include all associated projects, disciplines, parts, components, and third parties for this to work successfully. It is possible to provide extensive insight into the product and all its elements, as well as their accompanying vulnerabilities if done with pinpoint clarity and thoroughness throughout an entire organization.  

Components of a Software BOM

So, what needs to go into an SBOM? In principle, an open-source BOM needs to be a comprehensive itinerary of the building blocks used to build an application. The National Telecommunications and Information Administration (NTIA) has published a framework for software BOMs. It details the minimum requirements for software BOMs, guiding development houses towards developing more secure software. According to the NTIA, the minimum element can be divided into three main categories

Data fields

This element refers to the unique baseline information of the software which can be utilized to track it in the software BOM. This includes information such as:

  • The Software Author
  • The full name of the software
  • The current version of the software
  • Dependencies on other software
  • Date and time information of the software

Automation support

This element refers to the software’s capability to play a role in an automated development process as well as its compatibility across software ecosystems. This allows developers to define its scalability across a project.

Practices and processes

Organizations need to clearly define their practices and policies involved in the generation of the software BOM. They need to include metrics such as:

  • How frequently would the BOM be updated?
  • How the organization would handle the delivery of the applications.
  • Access control and identity metrics
  • Accommodation and mitigation of unknown risks that might arise through mistakes or other emerging factors.


Although the use of software BOM might seem excessive at first, it has valuable real-life applications and benefits. The greatest benefit derived from compiling a software BOM for each application build is the transparency with which applications can be crafted. A software BOM also allows an organization to accurately assess the risks involved when implementing open-source code segments and tools, effectively managing risk and improving compliance.

Work done by a Team Of Security Experts from Cyber Writes ( - World’s First Dedicated Content-as-a-Service (CaaS) Platform for Cybersecurity. For Exclusive Cyber Security Contents, Reach at: [email protected]