SBOM Submission Requirements

Defines in detail the standard SBOM format, required information, and PURL identifier rules under SK Telecom policy.

1. Standard Data Formats

SK Telecom supports both formats that have become established as global standards. Suppliers may choose and submit the format supported by the tool they use.

FormatVersionRecommended UseFile Format
CycloneDXv1.3, v1.4, v1.5, v1.6Application security, vulnerability management focusJSON (recommended), XML
SPDXv2.2, v2.3License compliance focusJSON, Tag-Value

Note: Both formats are recognized equally, but CycloneDX (JSON) format is recommended for internal system interoperability.

2. Required Information

The SBOM document you submit must include the following information. Missing information may result in rejection.

2.1 Metadata

Information about the document itself and the generation tool.

  • Timestamp: Generation date and time (ISO 8601 format)
  • Tool Info: Vendor, name, and version of the generation tool (e.g., CycloneDX-Maven-Plugin v2.7.9)
  • Component Info: Name and version of the top-level software being delivered

Generation Tool Specification Format

Generation tool information must be recorded in the following fields depending on the format.

  • SPDX: Record the tool name and version in the creationInfo.creators field with the Tool: prefix
  • CycloneDX: Record vendor, name, and version in the metadata.tools array
// SPDX creationInfo example
"creationInfo": {
  "created": "2026-04-06T03:22:00Z",
  "creators": ["Tool: Syft-0.98.0", "Organization: VendorName"]
}

2.2 Components

Information about the individual libraries that make up the software.

  • Name: Component name (e.g., commons-lang3)
  • Version: Component version (e.g., 3.12.0) — Required: Vulnerability mapping is impossible without the version
  • PURL (Package URL): [Required] Package identifier

Version information must be included. Each package/component must record its exact version in SPDX’s versionInfo field or CycloneDX’s version field. Without a version, mapping to the vulnerability database is impossible, so security analysis cannot be performed.

ItemAdditional Requirement
Version specificationRequired — Vulnerability mapping is impossible without the version

2.3 Dependency Scope

Important: Transitive dependencies must be included.

SK Telecom analyzes vulnerabilities based on the submitted SBOM. An SBOM that includes only direct dependencies may miss hidden vulnerabilities and may therefore be rejected.

Dependency TypeDescriptionInclusion
DirectLibraries explicitly declared by the projectRequired
TransitiveLibraries that the direct dependencies in turn depend onRequired
Dev-onlyLibraries not included at runtime, such as test and build toolsInclusion recommended

What are transitive dependencies?

For example, if a project uses library-A directly, and library-A internally uses library-B, then library-B is a transitive dependency. Even if library-B has a vulnerability, it cannot be detected unless it is included in the SBOM.

MyApp
  └─ library-A v1.0 (direct dependency)  ← explicitly declared by the supplier
       └─ library-B v2.3 (transitive dependency)  ← must be included in the SBOM
            └─ library-C v0.9 (transitive dependency)  ← must be included in the SBOM

Prerequisites for generating a correct SBOM

For transitive dependencies to be included accurately, the SBOM must be generated with the build (or package installation) completed. When only source code is present, transitive dependencies may be omitted.

  • Java (Maven): Generate after running mvn package or mvn dependency:resolve
  • Java (Gradle): Generate after running ./gradlew dependencies
  • Python: Generate after pip install -r requirements.txt (with the virtual environment activated)
  • Node.js: Generate after running npm install or yarn install
  • Go: Generate after running go mod download

For how to include transitive dependencies with each tool, refer to the Using Open Source Tools guide.

3. Package URL (PURL) Compliance

PURL (Package URL) is a standard URL format for uniquely identifying a software package. SK Telecom’s vulnerability analysis system operates based on PURL, so a valid PURL must be included for every component.

A PURL must be in the standard format beginning with the pkg: prefix. Free text such as name:version or org/repo:tag is not allowed; in such cases vulnerability mapping is impossible and the SBOM will be rejected.

PURL Examples by Language

EcosystemPURL Format Example
Java (Maven)pkg:maven/org.springframework/spring-core@5.3.20
JavaScript (NPM)pkg:npm/express@4.18.2
Python (PyPI)pkg:pypi/django@4.1.0
Gopkg:golang/github.com/gin-gonic/gin@v1.8.1
.NET (NuGet)pkg:nuget/Newtonsoft.Json@13.0.1
Ruby (RubyGems)pkg:gem/rails@7.0.4
GitHub (Actions / source hosting)pkg:github/actions/checkout@v3
OS package (RPM)pkg:rpm/centos/glibc@2.17-317.el7?arch=x86_64

PURL Type Restrictions

The purl must be of a type that can identify the ecosystem.

ItemRequirement
purl typeDo not use pkg:generic/. You must use a type that specifies the ecosystem
Allowed typespkg:rpm/, pkg:deb/, pkg:apk/, pkg:npm/, pkg:maven/, pkg:pypi/, pkg:cargo/, pkg:golang/, pkg:gem/, pkg:nuget/, pkg:github/ (source components hosted on GitHub), etc.

Correct / Incorrect PURL Examples

IncorrectCorrect
commons-lang3:3.12.0pkg:maven/org.apache.commons/commons-lang3@3.12.0
actions/checkout:v3pkg:github/actions/checkout@v3
lodash@4.17.21pkg:npm/lodash@4.17.21
pkg:generic/foo@1.0(Change to a type appropriate for the ecosystem)

For detailed PURL specifications, refer to the official Package URL spec.

4. Sample Document

CycloneDX Sample

{
  "bomFormat": "CycloneDX",
  "specVersion": "1.4",
  "version": 1,
  "metadata": {
    "timestamp": "2023-10-15T10:30:00Z",
    "tools": [{
      "vendor": "Example Corp",
      "name": "cyclonedx-maven-plugin",
      "version": "2.7.9"
    }],
    "component": {
      "type": "application",
      "name": "PaymentModule",
      "version": "2.1.0",
      "purl": "pkg:maven/com.example/payment-module@2.1.0"
    }
  },
  "components": [{
    "type": "library",
    "name": "spring-core",
    "version": "5.3.20",
    "purl": "pkg:maven/org.springframework/spring-core@5.3.20",
    "licenses": [{
      "license": {
        "id": "Apache-2.0"
      }
    }]
  }]
}
...

References