feat: add kube-chainsaw RBAC privilege chain analysis template

.gitignore

@@ -13,3 +13,4 @@
 e2etests/test_helper
 dist/
 coverage.out
+.gopath-loader/

docs/generated/checks.md

@@ -302,6 +302,15 @@ minReplicas: 3
 **Remediation**: Set Job.spec.ttlSecondsAfterFinished. Unset CronJob.Spec.JobTemplate.Spec.ttlSecondsAfterFinished.
 
 **Template**: [job-ttl-seconds-after-finished](templates.md#ttlsecondsafterfinished-impact-for-standalone-and-managed-job-objects)
+## kube-chainsaw-rbac
+
+**Enabled by default**: No
+
+**Description**: Detects RBAC privilege escalation paths, dangerous verbs, sensitive resource access, and scope confusion using graph analysis powered by kube-chainsaw
+
+**Remediation**: Review the RBAC configuration and apply least-privilege principles. See https://ugiordan.github.io/kube-chainsaw/ for detailed remediation guidance per rule.
+
+**Template**: [kube-chainsaw](templates.md#rbac-privilege-chain-analysis)
 ## latest-tag
 
 **Enabled by default**: Yes

docs/generated/templates.md

@@ -475,6 +475,46 @@ KubeLinter supports the following templates:
 **Supported Objects**: JobLike
 
 
+## RBAC Privilege Chain Analysis
+
+**Key**: `kube-chainsaw`
+
+**Description**: Detects RBAC privilege escalation paths, dangerous verbs, sensitive resource access, and scope confusion using graph analysis
+
+**Supported Objects**: Any
+
+
+**Parameters**:
+
+```yaml
+- arrayElemType: string
+  description: ""
+  name: rules
+  negationAllowed: true
+  regexAllowed: true
+  required: false
+  type: array
+- arrayElemType: string
+  description: ""
+  name: excludeRules
+  negationAllowed: true
+  regexAllowed: true
+  required: false
+  type: array
+- description: ""
+  name: minSeverity
+  negationAllowed: true
+  regexAllowed: true
+  required: false
+  type: string
+- description: ""
+  name: suppressionsFile
+  negationAllowed: true
+  regexAllowed: true
+  required: false
+  type: string
+```
+
 ## kubeconform
 
 **Key**: `kubeconform`

e2etests/bats-tests.sh

@@ -474,6 +474,21 @@ get_value_from() {
   [[ "${count}" == "2" ]]
 }
 
+@test "kube-chainsaw-rbac" {
+  tmp="tests/checks/kube-chainsaw/cluster-admin-pod.yaml"
+  cmd="${KUBE_LINTER_BIN} lint --include kube-chainsaw-rbac --do-not-auto-add-defaults --format json ${tmp}"
+  run ${cmd}
+
+  print_info "${status}" "${output}" "${cmd}" "${tmp}"
+  [ "$status" -eq 1 ]
+
+  message1=$(get_value_from "${lines[0]}" '.Reports[0].Diagnostic.Message')
+  count=$(get_value_from "${lines[0]}" '.Reports | length')
+
+  [[ "${message1}" == *"cluster-admin"* ]]
+  [[ "${count}" -ge "1" ]]
+}
+
 @test "latest-tag" {
   tmp="tests/checks/latest-tag.yml"
   cmd="${KUBE_LINTER_BIN} lint --include latest-tag --do-not-auto-add-defaults --format json ${tmp}"

e2etests/kube_chainsaw_test.go

@@ -0,0 +1,61 @@
+//go:build e2e
+
+package e2etests
+
+import (
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// TestKubeChainsawIntegration verifies that the kube-chainsaw template
+// integrates correctly with kube-linter and detects RBAC issues.
+func TestKubeChainsawIntegration(t *testing.T) {
+	kubeLinterBin := os.Getenv(kubeLinterBinEnv)
+	require.NotEmpty(t, kubeLinterBin, "Please set %s", kubeLinterBinEnv)
+
+	_, err := os.Stat(kubeLinterBin)
+	require.NoError(t, err)
+
+	// Test fixture with ServiceAccount, ClusterRoleBinding to cluster-admin, and Pod
+	fixtureDir := filepath.Join("..", "tests", "checks", "kube-chainsaw")
+
+	// Run kube-linter with kube-chainsaw-rbac check enabled
+	kubeLinterOut, err := exec.Command(
+		kubeLinterBin,
+		"lint",
+		fixtureDir,
+		"--include", "kube-chainsaw-rbac",
+	).CombinedOutput()
+
+	// kube-linter should exit with error code 1 when findings are detected
+	require.Error(t, err)
+	exitErr, ok := err.(*exec.ExitError)
+	require.True(t, ok)
+	outAsStr := string(kubeLinterOut)
+
+	assert.Equal(t, 1, exitErr.ExitCode(),
+		"unexpected exit code: %d; output from kube-linter: %v",
+		exitErr.ExitCode(), outAsStr)
+
+	// Verify that cluster-admin finding is detected
+	assert.Contains(t, outAsStr, "cluster-admin privileges",
+		"expected cluster-admin privileges finding in output: %s", outAsStr)
+
+	// Verify severity is critical
+	assert.True(t, strings.Contains(outAsStr, "CRITICAL") || strings.Contains(outAsStr, "critical"),
+		"expected 'critical' severity in output: %s", outAsStr)
+
+	// Verify the finding references the dangerous pod
+	assert.Contains(t, outAsStr, "privileged-pod",
+		"expected finding to reference 'privileged-pod': %s", outAsStr)
+
+	// Verify the kube-chainsaw-rbac check ran
+	assert.Contains(t, outAsStr, "kube-chainsaw-rbac",
+		"expected kube-chainsaw-rbac check in output: %s", outAsStr)
+}

go.mod

@@ -21,6 +21,7 @@ require (
 	github.com/spf13/pflag v1.0.10
 	github.com/spf13/viper v1.21.0
 	github.com/stretchr/testify v1.11.1
+	github.com/ugiordan/kube-chainsaw v1.0.0
 	github.com/yannh/kubeconform v0.8.0
 	helm.sh/helm/v3 v3.21.1
 	k8s.io/api v0.35.4

go.sum

@@ -356,6 +356,8 @@ github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
 github.com/subosito/gotenv v1.6.0 h1:9NlTDc1FTs4qu0DDq7AEtTPNw6SVm7uBMsUCUjABIf8=
 github.com/subosito/gotenv v1.6.0/go.mod h1:Dk4QP5c2W3ibzajGcXpNraDfq2IrhjMIvMSWPKKo0FU=
+github.com/ugiordan/kube-chainsaw v1.0.0 h1:m6m11HZfaMq2+liCQa9HEia1hCS93nj7zaH39fFfYas=
+github.com/ugiordan/kube-chainsaw v1.0.0/go.mod h1:/24yJCO1sPpQyfzN4RCMTTH9q2xT1WJGd414OmBhOG4=
 github.com/vmihailenco/msgpack/v4 v4.3.12/go.mod h1:gborTTJjAo/GWTqqRjrLCn9pgNN+NXzzngzBKDPIqw4=
 github.com/vmihailenco/tagparser v0.1.1/go.mod h1:OeAg3pn3UbLjkWt+rN9oFYB6u/cQgqMEUPoW2WPyhdI=
 github.com/x448/float16 v0.8.4 h1:qLwI1I70+NjRFUR3zs1JPUCgaCXSh3SW62uAKT1mSBM=

pkg/builtinchecks/yamls/kube-chainsaw-rbac.yaml

@@ -0,0 +1,8 @@
+name: "kube-chainsaw-rbac"
+description: "Detects RBAC privilege escalation paths, dangerous verbs, sensitive resource access, and scope confusion using graph analysis powered by kube-chainsaw"
+remediation: "Review the RBAC configuration and apply least-privilege principles. See https://ugiordan.github.io/kube-chainsaw/ for detailed remediation guidance per rule."
+scope:
+  objectKinds:
+    - Any
+template: "kube-chainsaw"
+params: {}

pkg/command/lint/command.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"strings"
+	"text/template"
 
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
@@ -25,15 +26,26 @@ const (
 	plainTemplateStr = `KubeLinter {{.Summary.KubeLinterVersion}}
 
 {{range .Reports}}
-{{- .Object.Metadata.FilePath | bold}}: (object: {{.Object.GetK8sObjectName | bold}}) {{.Diagnostic.Message | red}} (check: {{.Check | yellow}}, remediation: {{.Remediation | yellow}})
+{{- .Object.Metadata.FilePath | bold}}: (object: {{.Object.GetK8sObjectName | bold}}) {{if .Diagnostic.Severity}}[{{.Diagnostic.Severity | toUpper}}] {{end}}{{.Diagnostic.Message | red}} (check: {{.Check | yellow}}, remediation: {{effectiveRemediation . | yellow}})
 
 {{else}}No lint errors found!
 {{end -}}
 `
 )
 
 var (
-	plainTemplate = common.MustInstantiatePlainTemplate(plainTemplateStr, nil)
+	plainTemplate = common.MustInstantiatePlainTemplate(plainTemplateStr, template.FuncMap{
+		"toUpper": strings.ToUpper,
+		"effectiveRemediation": func(report diagnostic.WithContext) string {
+			// If Diagnostic.Metadata contains a remediation, use it; otherwise use the check's remediation
+			if report.Diagnostic.Metadata != nil {
+				if customRem, ok := report.Diagnostic.Metadata[diagnostic.MetaKeyRemediation]; ok && customRem != "" {
+					return customRem
+				}
+			}
+			return report.Remediation
+		},
+	})
 
 	formatters = common.Formatters{
 		Formatters: map[common.FormatType]common.FormatFunc{

pkg/command/lint/plain_format_test.go

@@ -0,0 +1,162 @@
+package lint
+
+import (
+	"bytes"
+	"strings"
+	"testing"
+	"time"
+
+	"golang.stackrox.io/kube-linter/pkg/diagnostic"
+	"golang.stackrox.io/kube-linter/pkg/lintcontext"
+	"golang.stackrox.io/kube-linter/pkg/run"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+)
+
+// TestPlainFormat_SeverityPrefix verifies that Diagnostic.Severity appears
+// as a prefix in plain output when present.
+func TestPlainFormat_SeverityPrefix(t *testing.T) {
+	tests := []struct {
+		name           string
+		severity       string
+		expectedPrefix string
+	}{
+		{"Critical", "critical", "[CRITICAL]"},
+		{"High", "high", "[HIGH]"},
+		{"Warning", "warning", "[WARNING]"},
+		{"Info", "info", "[INFO]"},
+		{"Empty", "", ""},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := run.Result{
+				Summary: run.Summary{
+					KubeLinterVersion: "test-version",
+					ChecksStatus:      run.ChecksPassed,
+					CheckEndTime:      time.Now().UTC(),
+				},
+				Reports: []diagnostic.WithContext{
+					{
+						Diagnostic: diagnostic.Diagnostic{
+							Message:  "test message",
+							Severity: tt.severity,
+						},
+						Check:       "test-check",
+						Remediation: "test remediation",
+						Object: lintcontext.Object{
+							Metadata: lintcontext.ObjectMetadata{
+								FilePath: "test.yaml",
+							},
+							K8sObject: &unstructured.Unstructured{
+								Object: map[string]interface{}{
+									"apiVersion": "v1",
+									"kind":       "Pod",
+									"metadata": map[string]interface{}{
+										"name":      "test-pod",
+										"namespace": "default",
+									},
+								},
+							},
+						},
+					},
+				},
+			}
+
+			var buf bytes.Buffer
+			err := plainTemplate.Execute(&buf, result)
+			if err != nil {
+				t.Fatalf("plainTemplate.Execute failed: %v", err)
+			}
+
+			output := buf.String()
+			if tt.expectedPrefix != "" {
+				if !strings.Contains(output, tt.expectedPrefix) {
+					t.Errorf("expected output to contain %q, got:\n%s", tt.expectedPrefix, output)
+				}
+			}
+
+			// Always verify message is present
+			if !strings.Contains(output, "test message") {
+				t.Errorf("expected output to contain message, got:\n%s", output)
+			}
+		})
+	}
+}
+
+// TestPlainFormat_EffectiveRemediation verifies that when Diagnostic.Metadata
+// contains a remediation, it overrides the check's default remediation.
+func TestPlainFormat_EffectiveRemediation(t *testing.T) {
+	tests := []struct {
+		name                string
+		checkRemediation    string
+		metadataRemediation string
+		expectedInOutput    string
+	}{
+		{
+			name:                "UseCheckRemediation",
+			checkRemediation:    "default remediation",
+			metadataRemediation: "",
+			expectedInOutput:    "default remediation",
+		},
+		{
+			name:                "UseMetadataRemediation",
+			checkRemediation:    "default remediation",
+			metadataRemediation: "custom remediation",
+			expectedInOutput:    "custom remediation",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			diag := diagnostic.Diagnostic{
+				Message: "test message",
+			}
+			if tt.metadataRemediation != "" {
+				diag.Metadata = map[string]string{
+					diagnostic.MetaKeyRemediation: tt.metadataRemediation,
+				}
+			}
+
+			result := run.Result{
+				Summary: run.Summary{
+					KubeLinterVersion: "test-version",
+					ChecksStatus:      run.ChecksPassed,
+					CheckEndTime:      time.Now().UTC(),
+				},
+				Reports: []diagnostic.WithContext{
+					{
+						Diagnostic:  diag,
+						Check:       "test-check",
+						Remediation: tt.checkRemediation,
+						Object: lintcontext.Object{
+							Metadata: lintcontext.ObjectMetadata{
+								FilePath: "test.yaml",
+							},
+							K8sObject: &unstructured.Unstructured{
+								Object: map[string]interface{}{
+									"apiVersion": "v1",
+									"kind":       "Pod",
+									"metadata": map[string]interface{}{
+										"name":      "test-pod",
+										"namespace": "default",
+									},
+								},
+							},
+						},
+					},
+				},
+			}
+
+			var buf bytes.Buffer
+			err := plainTemplate.Execute(&buf, result)
+			if err != nil {
+				t.Fatalf("plainTemplate.Execute failed: %v", err)
+			}
+
+			output := buf.String()
+			if !strings.Contains(output, tt.expectedInOutput) {
+				t.Errorf("expected output to contain %q, got:\n%s", tt.expectedInOutput, output)
+			}
+		})
+	}
+}