diff --git a/submit_app/processjar.py b/submit_app/processjar.py
index 65f2ee188..3ef6764ae 100755
--- a/submit_app/processjar.py
+++ b/submit_app/processjar.py
@@ -35,9 +35,11 @@ def process_jar(jar_file, expect_app_name):
         LOGGER.info('User uploaded invalid jar file: ' + str(bzf))
         raise ValueError('is not a valid zip file')
 
-    manifest_file = archive.read(_MANIFEST_FILE_NAME)
-    manifest = parse_manifest(manifest_file)
-    archive.close()
+    # FIX: Context manager guarantees the ZipFile is closed 
+    # and the file descriptor is released even if an exception occurs
+    with archive:
+        manifest_file = archive.read(_MANIFEST_FILE_NAME)
+        manifest = parse_manifest(manifest_file)
 
     is_osgi_bundle = True if manifest.main_section[b'Bundle-SymbolicName'] else False
     parser_func = _parse_osgi_bundle # if is_osgi_bundle else _parse_simple_app
@@ -190,4 +192,4 @@ def _parse_osgi_bundle(manifest):
         has_export_pkg_str = None
     has_export_pkg = True if has_export_pkg_str else False
 
-    return (app_name, app_version, app_works_with, app_dependencies, has_export_pkg)
+    return (app_name, app_version, app_works_with, app_dependencies, has_export_pkg)
\ No newline at end of file