diff --git a/lib/contextify.js b/lib/contextify.js
index 8171202..d6ba2f2 100644
--- a/lib/contextify.js
+++ b/lib/contextify.js
@@ -560,8 +560,15 @@ Decontextify.value = (value, traps, deepTraps, flags, mock) => {
 			case 'undefined':
 				return undefined;
 
-			default: // string, number, boolean, symbol
+			case 'string':
+			case 'number':
+			case 'boolean':
+			case 'symbol':
+			case 'bigint':
 				return value;
+
+			default: // new, unknown types can be dangerous
+				return null;
 		}
 	} catch (ex) {
 		// Never pass the handled exception through! This block can't throw an exception under normal conditions.
@@ -945,8 +952,15 @@ Contextify.value = (value, traps, deepTraps, flags, mock) => {
 			case 'undefined':
 				return undefined;
 
-			default: // string, number, boolean, symbol
+			case 'string':
+			case 'number':
+			case 'boolean':
+			case 'symbol':
+			case 'bigint':
 				return value;
+
+			default: // new, unknown types can be dangerous
+				return null;
 		}
 	} catch (ex) {
 		// Never pass the handled exception through! This block can't throw an exception under normal conditions.