MAL-2026-6208 Malicious code in fastercoding (PyPI)

The package exposes a single public function run() (re-exported from init.py) which, on Windows, downloads BackgroundSyncService.exe from https://raw.githubusercontent.com/manhhungdev0603/kl.py/refs/heads/main/BackgroundSyncService.exe, writes it to %PROGRAMDATA%\BackgroundSyncService, and executes it via subprocess.Popen([local_filepath], shell=True) (fastercoding/core.py lines 7 and 21). The source is a personal GitHub user's repo named 'kl.py' on the mutable main branch with no hash or signature verification, and the dropped binary is given a system-service cover name ('BackgroundSyncService') and staged into PROGRAMDATA — shape consistent with a keylogger/persistence dropper. Package metadata is empty (no description, author, or homepage) and the package contains no other functionality — the dropper is the package's entire purpose. Any caller of the only advertised entrypoint executes attacker-controlled, mutable, unsigned code on their machine.

The package contains code to download and run a malicious executable. The executable contains a remote access trojan controlled via Telegram bot, with capabilities like a keylogger, screen recording, command execution. It also attempts to gain persistence via startup registry keys.

Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.

Campaign: 2026-06-fastercode

Reasons (based on the campaign):

• Downloads and executes a remote executable.

• peristence-autorun

• uses-telegram-bot

• keylogger

• rat

• spyware-like