diff --git a/app/classes/shared/helpers.py b/app/classes/shared/helpers.py
index 65bc853a..489115ae 100644
--- a/app/classes/shared/helpers.py
+++ b/app/classes/shared/helpers.py
@@ -507,9 +507,9 @@ class Helpers:
 
         return mounts
 
-    def is_subdir(self, server_path, root_dir):
-        server_path = os.path.realpath(server_path)
-        root_dir = os.path.realpath(root_dir)
+    def is_subdir(self, child_path, parent_path):
+        server_path = os.path.realpath(child_path)
+        root_dir = os.path.realpath(parent_path)
 
         if self.is_os_windows():
             try:
@@ -1244,22 +1244,6 @@ class Helpers:
             return temp_dir
         return False
 
-    @staticmethod
-    def in_path(parent_path, child_path):
-        # Smooth out relative path names, note: if you are concerned about
-        # symbolic links, you should use os.path.realpath too
-        parent_path = os.path.abspath(parent_path)
-        child_path = os.path.abspath(child_path)
-
-        # Compare the common path of the parent and child path with the
-        # common path of just the parent path. Using the commonpath method
-        # on just the parent path will regularise the path name in the same way
-        # as the comparison that deals with both paths, removing any trailing
-        # path separator
-        return os.path.commonpath([parent_path]) == os.path.commonpath(
-            [parent_path, child_path]
-        )
-
     @staticmethod
     def download_file(executable_url, jar_path):
         try:
diff --git a/app/classes/web/ajax_handler.py b/app/classes/web/ajax_handler.py
index e3da33a8..9983f4fa 100644
--- a/app/classes/web/ajax_handler.py
+++ b/app/classes/web/ajax_handler.py
@@ -656,13 +656,14 @@ class AjaxHandler(BaseHandler):
 
             server_info = self.controller.servers.get_server_data_by_id(server_id)
             if not (
-                Helpers.in_path(
-                    Helpers.get_os_understandable_path(server_info["path"]), file_path
+                file_path,
+                Helpers.is_subdir(
+                    Helpers.get_os_understandable_path(server_info["path"])
                 )
-                or Helpers.in_path(
-                    Helpers.get_os_understandable_path(server_info["backup_path"]),
+                or Helpers.is_subdir(
                     file_path,
-                )
+                    Helpers.get_os_understandable_path(server_info["backup_path"]),
+                ),
             ) or not Helpers.check_file_exists(os.path.abspath(file_path)):
                 logger.warning(f"Invalid path in del_backup ajax call ({file_path})")
                 Console.warning(f"Invalid path in del_backup ajax call ({file_path})")
diff --git a/app/classes/web/file_handler.py b/app/classes/web/file_handler.py
index 5cf4df9e..ac5d2bf0 100644
--- a/app/classes/web/file_handler.py
+++ b/app/classes/web/file_handler.py
@@ -57,11 +57,11 @@ class FileHandler(BaseHandler):
                 return
             server_id = bleach.clean(server_id)
 
-            if not Helpers.in_path(
+            if not Helpers.is_subdir(
+                file_path,
                 Helpers.get_os_understandable_path(
                     self.controller.servers.get_server_data_by_id(server_id)["path"]
                 ),
-                file_path,
             ) or not Helpers.check_file_exists(os.path.abspath(file_path)):
                 logger.warning(
                     f"Invalid path in get_file file file ajax call ({file_path})"
@@ -163,11 +163,11 @@ class FileHandler(BaseHandler):
                 return
             server_id = bleach.clean(server_id)
 
-            if not Helpers.in_path(
+            if not Helpers.is_subdir(
+                file_path,
                 Helpers.get_os_understandable_path(
                     self.controller.servers.get_server_data_by_id(server_id)["path"]
                 ),
-                file_path,
             ) or Helpers.check_file_exists(os.path.abspath(file_path)):
                 logger.warning(
                     f"Invalid path in create_file file ajax call ({file_path})"
@@ -196,11 +196,11 @@ class FileHandler(BaseHandler):
                 return
             server_id = bleach.clean(server_id)
 
-            if not Helpers.in_path(
+            if not Helpers.is_subdir(
+                dir_path,
                 Helpers.get_os_understandable_path(
                     self.controller.servers.get_server_data_by_id(server_id)["path"]
                 ),
-                dir_path,
             ) or Helpers.check_path_exists(os.path.abspath(dir_path)):
                 logger.warning(
                     f"Invalid path in create_dir file ajax call ({dir_path})"
@@ -263,12 +263,12 @@ class FileHandler(BaseHandler):
 
             server_info = self.controller.servers.get_server_data_by_id(server_id)
             if not (
-                Helpers.in_path(
-                    Helpers.get_os_understandable_path(server_info["path"]), file_path
+                Helpers.is_subdir(
+                    file_path, Helpers.get_os_understandable_path(server_info["path"])
                 )
-                or Helpers.in_path(
-                    Helpers.get_os_understandable_path(server_info["backup_path"]),
+                or Helpers.is_subdir(
                     file_path,
+                    Helpers.get_os_understandable_path(server_info["backup_path"]),
                 )
             ) or not Helpers.check_file_exists(os.path.abspath(file_path)):
                 logger.warning(f"Invalid path in del_file file ajax call ({file_path})")
@@ -296,8 +296,8 @@ class FileHandler(BaseHandler):
             server_id = bleach.clean(server_id)
 
             server_info = self.controller.servers.get_server_data_by_id(server_id)
-            if not Helpers.in_path(
-                Helpers.get_os_understandable_path(server_info["path"]), dir_path
+            if not Helpers.is_subdir(
+                dir_path, Helpers.get_os_understandable_path(server_info["path"])
             ) or not Helpers.check_path_exists(os.path.abspath(dir_path)):
                 logger.warning(f"Invalid path in del_file file ajax call ({dir_path})")
                 Console.warning(f"Invalid path in del_file file ajax call ({dir_path})")
@@ -348,11 +348,11 @@ class FileHandler(BaseHandler):
                 return
             server_id = bleach.clean(server_id)
 
-            if not Helpers.in_path(
+            if not Helpers.is_subdir(
+                file_path,
                 Helpers.get_os_understandable_path(
                     self.controller.servers.get_server_data_by_id(server_id)["path"]
                 ),
-                file_path,
             ) or not Helpers.check_file_exists(os.path.abspath(file_path)):
                 logger.warning(
                     f"Invalid path in save_file file ajax call ({file_path})"
@@ -387,11 +387,11 @@ class FileHandler(BaseHandler):
                 Console.warning("Invalid path(s) in rename_file file ajax call")
                 return
 
-            if not Helpers.in_path(
+            if not Helpers.is_subdir(
+                item_path,
                 Helpers.get_os_understandable_path(
                     self.controller.servers.get_server_data_by_id(server_id)["path"]
                 ),
-                item_path,
             ) or not Helpers.check_path_exists(os.path.abspath(item_path)):
                 logger.warning(
                     f"Invalid old name path in rename_file file ajax call ({server_id})"
@@ -403,11 +403,11 @@ class FileHandler(BaseHandler):
 
             new_item_path = os.path.join(os.path.split(item_path)[0], new_item_name)
 
-            if not Helpers.in_path(
+            if not Helpers.is_subdir(
+                new_item_path,
                 Helpers.get_os_understandable_path(
                     self.controller.servers.get_server_data_by_id(server_id)["path"]
                 ),
-                new_item_path,
             ) or Helpers.check_path_exists(os.path.abspath(new_item_path)):
                 logger.warning(
                     f"Invalid new name path in rename_file file ajax call ({server_id})"
@@ -462,11 +462,11 @@ class FileHandler(BaseHandler):
                 Console.warning("Invalid path(s) in rename_file file ajax call")
                 return
 
-            if not Helpers.in_path(
+            if not Helpers.is_subdir(
+                item_path,
                 Helpers.get_os_understandable_path(
                     self.controller.servers.get_server_data_by_id(server_id)["path"]
                 ),
-                item_path,
             ) or not Helpers.check_path_exists(os.path.abspath(item_path)):
                 logger.warning(
                     f"Invalid old name path in rename_file file ajax call ({server_id})"
@@ -478,11 +478,11 @@ class FileHandler(BaseHandler):
 
             new_item_path = os.path.join(os.path.split(item_path)[0], new_item_name)
 
-            if not Helpers.in_path(
+            if not Helpers.is_subdir(
+                new_item_path,
                 Helpers.get_os_understandable_path(
                     self.controller.servers.get_server_data_by_id(server_id)["path"]
                 ),
-                new_item_path,
             ) or Helpers.check_path_exists(os.path.abspath(new_item_path)):
                 logger.warning(
                     f"Invalid new name path in rename_file file ajax call ({server_id})"
diff --git a/app/classes/web/panel_handler.py b/app/classes/web/panel_handler.py
index df58263d..bb91eb94 100644
--- a/app/classes/web/panel_handler.py
+++ b/app/classes/web/panel_handler.py
@@ -821,9 +821,9 @@ class PanelHandler(BaseHandler):
                     Helpers.get_os_understandable_path(server_info["backup_path"]), file
                 )
             )
-            if not Helpers.in_path(
-                Helpers.get_os_understandable_path(server_info["backup_path"]),
+            if not Helpers.is_subdir(
                 backup_file,
+                Helpers.get_os_understandable_path(server_info["backup_path"]),
             ) or not os.path.isfile(backup_file):
                 self.redirect("/panel/error?error=Invalid path detected")
                 return
@@ -1476,8 +1476,9 @@ class PanelHandler(BaseHandler):
 
             server_info = self.controller.servers.get_server_data_by_id(server_id)
 
-            if not Helpers.in_path(
-                Helpers.get_os_understandable_path(server_info["path"]), file
+            if not Helpers.is_subdir(
+                file,
+                Helpers.get_os_understandable_path(server_info["path"]),
             ) or not os.path.isfile(file):
                 self.redirect("/panel/error?error=Invalid path detected")
                 return
diff --git a/app/classes/web/upload_handler.py b/app/classes/web/upload_handler.py
index 39752a35..e23db114 100644
--- a/app/classes/web/upload_handler.py
+++ b/app/classes/web/upload_handler.py
@@ -278,11 +278,11 @@ class UploadHandler(BaseHandler):
             filename = self.request.headers.get("X-FileName", None)
             full_path = os.path.join(path, filename)
 
-            if not Helpers.in_path(
+            if not Helpers.is_subdir(
+                full_path,
                 Helpers.get_os_understandable_path(
                     self.controller.servers.get_server_data_by_id(server_id)["path"]
                 ),
-                full_path,
             ):
                 logger.warning(
                     f"User {user_id} tried to upload a file to {server_id} "