Software Bill of Materials (SBOM)
A “software bill of materials” (SBOM) has emerged as a key building block in software security and software supply chain risk management. A SBOM is a nested inventory, a list of ingredients that make up software components. The SBOM work has advanced since 2018 as a collaborative community effort, driven by National Telecommunications and Information Administration’s (NTIA) multistakeholder process.
CISA will advance the SBOM work by facilitating community engagement, development, and progress, with a focus on scaling and operationalization, as well as tools, new technologies, and new use cases. This website will also be a nexus for the broader set of SBOM resources across the digital ecosystem and around the world.
An SBOM-related concept is the Vulnerability Exploitability eXchange (VEX). A VEX document is an attestation, a form of a security advisory that indicates whether a product or products are affected by a known vulnerability or vulnerabilities.
CISA SBOM Workstreams
CISA recognizes the importance of SBOMs in transparency and security, and that SBOM evolution and refinement should come from the community. To launch this community work, CISA is facilitating four new workstreams around SBOM, which are intended to advance the software and security communities’ understanding of SBOM creation, use, and implementation across the broader technology ecosystem. CISA will act as a facilitator and participants will drive the outcomes, including any specific issues of focus or next steps.
- Cloud & Online Applications
Meeting Day/Time: Wednesday 3 PM ET – 4 PM ET (weekly)
The Cloud and Online Applications workstream will focus on integrating current understanding around SBOM into the context of online applications and modern infrastructure. Most of the existing discussion around SBOM, particularly around SBOM use cases, has focused on on-premise software. Cloud and Software-as-a-Service (SaaS)-based software comprises a large and growing segment of the software ecosystem. It will be important to integrate the current understanding of SBOM with emergent advances in cloud-native technologies to tell better stories about SBOM use cases for cloud and understand how this will be handled across organizational boundaries.
- On-Ramps & Adoption
Meeting Day/Time: Tuesday 12 PM ET – 1 PM ET (weekly)
The On-Ramps and Adoption workstream will focus on promoting education and awareness to help lower the costs and complexities of adoption, allowing newer or less mature organizations to provide, request, and use SBOMs to secure and understand their organization’s risk. The workstream may also define use cases for SBOM, as well as coordinate efforts across all new and existing SBOM-related workstreams to assist in marketing as well as help to avoid substantive overlap.
- Sharing & Exchanging
Meeting Day/Time: Monday 12 PM ET – 1 PM ET (weekly)
The Sharing and Exchanging workstream will focus on the topic of moving SBOMs, and related metadata, across the software supply chain. The community will have discussions centered around understanding how to enable discovery and access, while underscoring the importance of solution interoperability.
- Tooling & Implementation
Meeting Day/Time: Thursday 3 PM ET – 4 PM ET (weekly)
The Tooling and Implementation workstream will focus on opportunities and challenges for automating the SBOM ecosystem. This ecosystem will be driven by a range of accessible and constructive tools and enabling applications, both open source and proprietary. This work will potentially enhance existing SBOM data with further implementation details, encourage interoperability across tools and uses, and foster the advancement and efficiency of the tooling marketplace.
For information about the “NTIA Consensus” defining and implementing SBOM, drafted by stakeholders, see the resources at ntia.gov/sbom.
The “Minimum Elements” defined under Executive Order 14028 are available at the NTIA SBOM Publications page.
Past SBOM Events
A recap of the 2021 SBOM-a-rama and recordings of the event.
For summaries from the eight SBOM Listening Sessions held in September 2022, as detailed in the Federal Register Notice, please send a request to SBOM@cisa.dhs.gov.
Vulnerability Exploitability eXchange (VEX) Use Case Document (April 2022)
This resource provides the recommended minimum data elements of a VEX document and offers a set of scenarios with proposed implementations.
Vulnerability Exploitability eXchange (VEX) Status Justification Document (June 2022)
This resource provides the recommended NOT AFFECTED status justifications of a VEX document and offers the reader examples of when the different status justifications might be used.
For any questions or to receive updates on CISA’s SBOM work, please email SBOM@cisa.dhs.gov.