slashben / go-vex

Go module to generate and transform VEX documents

go-vex

Go library for generating, consuming, and operating on VEX documents

This repository contains the OpenVEX Go source code. This module lets authors create, modify and manage VEX documents.

The full documentation for this module can be found at https://pkg.go.dev/github.com/openvex/go-vex.

For more information about the OpenVEX specification implemented by this module, check out the OpenVEX specification.

Installing

Run go get to install the latest version of the library.

go get -u github.com/openvex/go-vex@latest

Example Usage: Generate a VEX Document

The following is a simple example showing how to generate a VEX document:

package main

import (
	"os"

	"github.com/openvex/go-vex/pkg/vex"
)

func main() {
	// Create new VEX document
	doc := vex.New()

	// Define the documenmt author
	doc.Author = "Wolfi J. Inkinson"
	doc.AuthorRole = "Senior VEXing Engineer"

	// Here, we add an impact statement. The core of VEX. We will inform
	// that our git image is not affected by CVE-2023-12345 and why:
	doc.Statements = append(doc.Statements, vex.Statement{
		// ... define the vulnerability:
		Vulnerability: vex.Vulnerability{
			ID:          "https://nvd.nist.gov/vuln/detail/CVE-2021-44228",
			Name:        "CVE-2021-44228",
			Description: "Remote code injection in Log4j",
			Aliases: []vex.VulnerabilityID{
				vex.VulnerabilityID("GHSA-jfh8-c2jp-5v3q"),
			},
		},

		// ... add an image as product:
		Products: []vex.Product{
			{
				Component: vex.Component{
					ID: "pkg:maven/org.springframework.boot/[email protected]",
					Identifiers: map[vex.IdentifierType]string{
						vex.PURL: "pkg:maven/org.springframework.boot/[email protected]",
					},
					Hashes: map[vex.Algorithm]vex.Hash{
						vex.SHA256: vex.Hash("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"),
					},
				},

				// ... specify optional subcomponents:
				// Subcomponents: []vex.Subcomponent{},
			},
			// "pkg:oci/git@sha256:23a264e6e429852221a963e9f17338ba3f5796dc7086e46439a6f4482cf6e0cb",
		},

		// ... choose one of the VEX status labels:
		Status: vex.StatusNotAffected,

		// ... finally, a machine-readable justification and optional statement:
		Justification:   vex.VulnerableCodeNotInExecutePath,
		ImpactStatement: "Spring Boot users are only affected by this vulnerability if they ...",
	})

	// Generate a canonical identifier for the VEX document:
	doc.GenerateCanonicalID()

	// Output the document to stdout:
	doc.ToJSON(os.Stdout)
}

Running this example renders the following simple VEX document:

{
  "@context": "https://openvex.dev/ns/v0.2.0",
  "@id": "https://openvex.dev/docs/public/vex-6ccf08fbf67f1489f201bb2b79a024b55d2ce07763098c78822f2f25283703d8",
  "author": "Wolfi J. Inkinson",
  "role": "Senior VEXing Engineer",
  "timestamp": "2023-09-21T15:32:30.728569-05:00",
  "version": 1,
  "statements": [
    {
      "vulnerability": {
        "@id": "https://nvd.nist.gov/vuln/detail/CVE-2021-44228",
        "name": "CVE-2021-44228",
        "description": "Remote code injection in Log4j",
        "aliases": [
          "GHSA-jfh8-c2jp-5v3q"
        ]
      },
      "products": [
        {
          "@id": "pkg:maven/org.springframework.boot/[email protected]",
          "hashes": {
            "sha-256": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
          },
          "identifiers": {
            "purl": "pkg:maven/org.springframework.boot/[email protected]"
          }
        }
      ],
      "status": "not_affected",
      "justification": "vulnerable_code_not_in_execute_path",
      "impact_statement": "Spring Boot users are only affected by this vulnerability if they ..."
    }
  ]
}