I built a real NTFS-level file locker in Python — no password needed to protect, and even I can't brute-force it
Most "file lock" apps on the market do one of two things: rename your file extension, or hide it in a folder. Both take about ten seconds to bypass with Windows Explorer's search bar. That bugged me enough to build something that actually works at the OS level. This is ATLOCK v4.0 — a total security suite for Windows, built in Python, and it's the fourth rebuild of a project I started from…
ATLOCK v4.0 is a new file locker app for Windows built entirely in Python. Unlike most other file lock apps, ATLOCK doesn't rely on password wrappers or renaming files. Instead, it manipulates the Windows NTFS ACL (Access Control List) at the system level to deny access to the files for every user, including SYSTEM. This means that even if someone tries to brute-force the master password, they can't access the files, because the OS itself is blocking them.
ATLOCK includes five modules: Lockdown, File Guard, Password Vault, Intruder Ops, and Settings. The Lockdown module provides a system-level screen lock with a countdown timer ranging from 10 minutes to 8 hours. The core File Guard module, as mentioned, is the one that actually locks files by rewriting their NTFS ACL. The Password Vault securely stores sensitive information like emails, UPI IDs, and PINs.
The Intruder Ops module captures photos and records videos if someone enters the wrong master password multiple times. The Settings module allows users to configure various options and controls for the gallery folder.
The security improvements in this version include replacing basic XOR encryption in the password vault with Fernet encryption (AES-128-CBC + HMAC), using PBKDF2-HMAC-SHA256 with 200,000 iterations and a random salt per vault for the master password, masking failed intrusion attempts, and encrypting alert credentials with a machine-bound key.
The app is built using customtkinter for the UI, cryptography for encryption algorithms, pywin32 for NTFS ACL manipulation, and opencv-python for capturing intruder footage. It's packaged as a standalone .exe using PyInstaller.
The creator, a 13-year-old developer, has rebuilt this project four times due to the need for better security. Akhouri Systems, the company behind ATLOCK, aims to provide security for everyday software that hasn't been properly maintained. You can check out the app and more information at the provided links.
Written by urgent.news from Dev.to's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
