check if mod.paths is defined before using it

packages/@aws-cdk/core/lib/private/runtime-info.ts

@@ -63,6 +63,15 @@ export function collectRuntimeInformation(): cxschema.RuntimeInfo {
  */
 function findNpmPackage(fileName: string): { name: string, version: string, private?: boolean } | undefined {
   const mod = require.cache[fileName];
+
+  if (!mod.paths) {
+    // sometimes this can be undefined. for example when querying for .json modules
+    // inside a jest runtime environment.
+    // see https://github.com/aws/aws-cdk/issues/7657
+    // potentially we can remove this if it turns out to be a bug in how jest implemented the 'require' module.
+    return undefined;
+  }
+
   const paths = mod.paths.map(stripNodeModules);
 
   try {