[BC-36908] CVSS v4 mappings support

CHANGELOG.md

@@ -14,6 +14,13 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/) and this p
 
 ### Removed
 
+## [v0.13.7](https://github.com/bugcrowd/vrt-ruby/compare/v0.13.6...v0.13.7) - 2026-03-05
+
+### Added
+
+- CVSS v4 mapping support: `cvss_v4` in `VRT::MAPPINGS` and `node.mappings[:cvss_v4]` when mapping data is present
+- Specs for cvss_v4 mappings (mapping file loading, `#get` for leaf/internal/root nodes, default, and node `#mappings`)
+
 ## [v0.13.6](https://github.com/bugcrowd/vrt-ruby/compare/v0.13.5...v0.13.6) - 2025-08-19
 
 ### Added

lib/vrt.rb

@@ -19,7 +19,7 @@ module VRT
                    'name' => 'Other',
                    'priority' => nil,
                    'type' => 'category' }.freeze
-  MAPPINGS = %i[cvss_v3 remediation_advice cwe].freeze
+  MAPPINGS = %i[cvss_v3 cvss_v4 remediation_advice cwe].freeze
 
   @version_json = {}
   @last_update = {}

spec/sample_vrt/2.0/mappings/cvss_v4.json

@@ -0,0 +1,78 @@
+{
+  "metadata": {
+    "default": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+  },
+  "content": [
+    {
+      "id": "server_security_misconfiguration",
+      "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
+      "children": [
+        {
+          "id": "unsafe_cross_origin_resource_sharing",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "ssl_attack_breach_poodle_etc",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "using_default_credentials",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "misconfigured_dns",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N"
+        }
+      ]
+    },
+    {
+      "id": "server_side_injection",
+      "children": [
+        {
+          "id": "file_inclusion",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "remote_code_execution_rce",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "sql_injection",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"
+        }
+      ]
+    },
+    {
+      "id": "unvalidated_redirects_and_forwards",
+      "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N",
+      "children": [
+        {
+          "id": "open_redirect",
+          "children": [
+            {
+              "id": "get_based",
+              "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N"
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "id": "dumb_v2_category",
+      "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "insecure_data_storage",
+      "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "broken_authentication_and_session_management",
+      "children": [
+        {
+          "id": "authentication_bypass",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
+        }
+      ]
+    }
+  ]
+}

spec/sample_vrt/999.999/mappings/cvss_v4/cvss_v4.json

@@ -0,0 +1,141 @@
+{
+  "metadata": {
+    "default": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+  },
+  "content": [
+    {
+      "id": "server_security_misconfiguration",
+      "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
+      "children": [
+        {
+          "id": "unsafe_cross_origin_resource_sharing",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "ssl_attack_breach_poodle_etc",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "using_default_credentials",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "misconfigured_dns",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N"
+        }
+      ]
+    },
+    {
+      "id": "server_side_injection",
+      "children": [
+        {
+          "id": "file_inclusion",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:L/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "remote_code_execution_rce",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"
+        },
+        {
+          "id": "sql_injection",
+          "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"
+        }
+      ]
+    },
+    {
+      "id": "unvalidated_redirects_and_forwards",
+      "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N",
+      "children": [
+        {
+          "id": "open_redirect",
+          "children": [
+            {
+              "id": "get_based",
+              "cvss_v4": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N"
+            }
+          ]
+        }
+      ]
+    },
+    {
+      "id": "broken_authentication_and_session_management",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "insecure_direct_object_references_idor",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "sensitive_data_exposure",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "cross_site_scripting_xss",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "missing_function_level_access_control",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "cross_site_request_forgery_csrf",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "application_level_denial_of_service_dos",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "external_behavior",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "insufficient_security_configurability",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "using_components_with_known_vulnerabilities",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "insecure_data_storage",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "lack_of_binary_hardening",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "insecure_data_transport",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "insecure_os_firmware",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "broken_cryptography",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "privacy_concerns",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "network_security_misconfiguration",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "mobile_security_misconfiguration",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "client_side_injection",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    },
+    {
+      "id": "vrt_category_only_in_test",
+      "cvss_v4": "CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N"
+    }
+  ]
+}

spec/vrt/mappings_spec.rb

@@ -15,6 +15,12 @@
       it { is_expected.not_to be nil }
     end
 
+    context 'when cvss_v4 mapping is nested under a subdirectory' do
+      let(:scheme) { :cvss_v4 }
+
+      it { is_expected.not_to be nil }
+    end
+
     context 'when mapping is in flat directory' do
       let(:scheme) { :cwe }
 
@@ -196,4 +202,66 @@
       end
     end
   end
+
+  describe 'cvss_v4_mapping' do
+    let(:cvss_v4) { described_class.new(:cvss_v4) }
+
+    describe '#get' do
+      subject { cvss_v4.get(id_list, version) }
+
+      context 'when cvss_v4 on leaf node' do
+        let(:id_list) { %i[unvalidated_redirects_and_forwards open_redirect get_based] }
+        let(:version) { '999.999' }
+
+        it 'returns the full CVSS v4 vector string' do
+          is_expected.to eq('CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N')
+        end
+      end
+
+      context 'when cvss_v4 on internal node' do
+        let(:id_list) { %i[server_security_misconfiguration unsafe_cross_origin_resource_sharing] }
+        let(:version) { '999.999' }
+
+        it 'returns the most specific cvss_v4 value' do
+          is_expected.to eq('CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N')
+        end
+      end
+
+      context 'when cvss_v4 on root node with children' do
+        let(:id_list) { %i[server_security_misconfiguration] }
+        let(:version) { '999.999' }
+
+        it 'returns the category-level cvss_v4 value' do
+          is_expected.to eq('CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N')
+        end
+      end
+
+      context 'when cvss_v4 on root node without children' do
+        let(:id_list) { %i[insecure_data_storage] }
+        let(:version) { '999.999' }
+
+        it 'returns the node cvss_v4 value' do
+          is_expected.to eq('CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N')
+        end
+      end
+
+      context 'when other' do
+        let(:id_list) { %i[other] }
+        let(:version) { '999.999' }
+
+        it 'returns the default from metadata' do
+          is_expected.to eq('CVSS:4.0/AV:P/AC:H/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N')
+        end
+      end
+
+      context 'when using version 2.0 flat mapping' do
+        let(:id_list) { %i[unvalidated_redirects_and_forwards open_redirect get_based] }
+        let(:version) { '2.0' }
+
+        it 'returns the cvss_v4 value for the leaf node' do
+          is_expected.to eq('CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N')
+        end
+      end
+    end
+  end
 end

spec/vrt/node_spec.rb

@@ -55,6 +55,14 @@
       end
     end
 
+    context 'cvss_v4' do
+      it 'has the expected cvss_v4 full vector string' do
+        expect(mappings).to include(
+          cvss_v4: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N'
+        )
+      end
+    end
+
     context 'remediation_advice' do
       let(:id) { 'server_security_misconfiguration.unsafe_cross_origin_resource_sharing' }