diff --git a/review/docmap_test.go b/review/docmap_test.go
index 99cb2c0..7ad51c0 100644
--- a/review/docmap_test.go
+++ b/review/docmap_test.go
@@ -376,6 +376,50 @@ func TestLoadMatchingDocs_Deduplication(t *testing.T) {
 	}
 }
 
+func TestValidateDocPath(t *testing.T) {
+	valid := []string{
+		"docs/design.md",
+		"docs/domain/contexts/risk/risk-controls.md",
+		"README.md",
+		"a/b/c",
+	}
+	for _, p := range valid {
+		if err := validateDocPath(p); err != nil {
+			t.Errorf("expected valid path %q to pass, got error: %v", p, err)
+		}
+	}
+
+	invalid := []string{
+		"/etc/passwd",
+		"/docs/design.md",
+		"docs/../../../etc/passwd",
+		"../sibling-repo/file.md",
+		"a/b/../c",
+	}
+	for _, p := range invalid {
+		if err := validateDocPath(p); err == nil {
+			t.Errorf("expected path %q to be rejected, but it was accepted", p)
+		}
+	}
+}
+
+func TestLoadMatchingDocs_PathTraversalRejected(t *testing.T) {
+	fetcher := &fakeDocFetcher{
+		files: map[string]string{
+			"../secret.md": "should not be fetched",
+		},
+	}
+	content, err := LoadMatchingDocs(context.Background(), fetcher, "owner", "repo",
+		[]string{"../secret.md"}, DocMapOptions{MaxBytes: DefaultDocMapMaxBytes})
+	if err != nil {
+		t.Fatalf("unexpected hard error: %v", err)
+	}
+	// Bad path should be skipped (warned), not injected.
+	if strings.Contains(content, "should not be fetched") {
+		t.Errorf("path traversal doc was injected, expected it to be skipped")
+	}
+}
+
 // ============================================================
 // Helpers
 // ============================================================