An SBOM (software bill of materials) is a list of the components inside a piece of software. SCA (software composition analysis) is the process of checking those components against vulnerability and license data. The SBOM is the inventory, SCA is the analysis, and many tools produce one while doing the other.
Definitions
SBOM. CISA describes it as a nested inventory, a list of ingredients that make up software components. It is a document you can store, send to a customer or feed to another tool.
SCA. A practice and a class of tools that identify open source components and check them for known vulnerabilities, license issues and age.
Vulnerability exploitability exchange (VEX). A companion statement that says whether a given product is actually affected by a known vulnerability. CISA describes it as an attestation, a form of security advisory.
How they relate
Think of a food label and a food safety check. The label lists ingredients. The check asks whether any ingredient is on a recall list. You can have a label without a check, which is an SBOM that nobody analyses. You can run a check without producing a label you can share, which is an internal SCA scan.
In practice a scan builds an inventory first. If the tool exports that inventory in a standard format, you now have an SBOM as a by-product.
Comparison
| Question | SCA | SBOM |
|---|---|---|
| What is it? | A process or tool | A document or data file |
| Main output | Findings with severity and fixes | A component list with versions |
| Who reads it | Developers, security teams | Customers, auditors, tools |
| Changes over time | Findings change as advisories arrive | Changes when the build changes |
| Needs vulnerability data | Yes | No |
When you need which
- You want to fix risk in your own code base. Run SCA, and accept that it builds its own inventory.
- A customer or regulator asks what is in your product. Produce an SBOM, and keep the format standard.
- You want to know if a new advisory touches a shipped product. Keep SBOMs for each release, then search them when the advisory lands.
- You want fewer false alarms. Pair findings with VEX statements or reachability evidence.
A short workflow
- Generate an SBOM at build time and store it with the release.
- Run SCA against that same inventory on a schedule.
- Record decisions on each finding, such as fixed, not affected or accepted.
- Share the SBOM, and the VEX statements where appropriate, when asked.
Try it yourself
Click through it at your own pace, or open it full screen.
Watch how the component inventory is built before any vulnerability is attached to it.
Quick check
Can an SBOM tell me which components are vulnerable?
Not by itself. It lists components. You need advisory data and a matching step, which is what SCA adds.
Do I need both?
Usually yes. SCA finds risk for your team, and an SBOM lets others see what you ship.
Safeguard covers SBOM and dependency scanning in one workflow. You can try a free scan to see the inventory it builds.
Sources
Last reviewed: 19 October 2026.
