MAL-2026-5273 Malicious code in anthropy (PyPI)
- Package
- anthropy
- Registry
- PyPI
What is MAL-2026-5273?
MAL-2026-5273 is a malicious package in anthropy, published on 5 Jun 2026.
Official description
The package anthropy is a one-character typosquat of the legitimate anthropic PyPI SDK. The sole module anthropy.py executes a classic Python reverse shell at import time: it opens a TCP socket to 54.176.251.240:9001, duplicates the socket file descriptor over stdin/stdout/stderr, and spawns an interactive sh via pty.spawn. The same payload also fires when the anthropy console script declared in pyproject.toml is invoked. The package ships no API surface matching its name (project summary is just 'hello world') — its only behavior is the reverse shell. Any developer who mistypes pip install anthropic and then imports the package, or runs the installed CLI, hands an interactive shell on their machine to the operator of 54.176.251.240.
During import, the package starts a reverse shell
Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2026-06-anthropy
Reasons (based on the campaign):
- The package contains code to create a reverse shell, allowing an attacker to execute any commands on the victim's machine.
What should I do about MAL-2026-5273?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.