diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9c895706..1d71ff63 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -54,6 +54,7 @@ _This release is scheduled to be released on 2025-01-01._
 - [core] Fix missing `basePath` where `location.host` is used (#3613)
 - [compliments] croner library changed filenames used in latest version (#3624)
 - [linter] Fix ESLint ignore pattern which caused that default modules not to be linted (#3632)
+- [core] Fix module path in case of sub/sub folder is used and use path.resolve for resolve `moduleFolder` and `defaultModuleFolder` in app.js (#3653)
 - [calendar] Update to resolve issues #3098 #3144 #3351 #3422 #3443 #3467 #3537 related to timezone changes
 - [calendar] Fix #3267 (styles array), also fixes event with both exdate AND recurrence(and testcase)
 - [calendar] Fix showEndsOnlyWithDuration not working, #3598, applies ONLY to full day events
diff --git a/js/app.js b/js/app.js
index 9d111c7e..0c2586af 100644
--- a/js/app.js
+++ b/js/app.js
@@ -164,10 +164,10 @@ function App () {
 		const elements = module.split("/");
 		const moduleName = elements[elements.length - 1];
 		const env = getEnvVarsAsObj();
-		let moduleFolder = `${__dirname}/../${env.modulesDir}/${module}`;
+		let moduleFolder = path.resolve(`${__dirname}/../${env.modulesDir}`, module);
 
 		if (defaultModules.includes(moduleName)) {
-			const defaultModuleFolder = `${__dirname}/../modules/default/${module}`;
+			const defaultModuleFolder = path.resolve(`${__dirname}/../modules/default/`, module);
 			if (process.env.JEST_WORKER_ID === undefined) {
 				moduleFolder = defaultModuleFolder;
 			} else {
@@ -178,7 +178,7 @@ function App () {
 			}
 		}
 
-		const moduleFile = `${moduleFolder}/${module}.js`;
+		const moduleFile = `${moduleFolder}/${moduleName}.js`;
 
 		try {
 			fs.accessSync(moduleFile, fs.R_OK);