anthropyPyPI
Advisory published Updated
anthropy is a confirmed malicious PyPI package (MAL-2026-5273) that steals credentials and exfiltrates sensitive data (malicious versions 0.0.1, 0.0.2, 0.0.3…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in anthropy (PyPI)
What this malware does
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.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for anthropy (6 malicious versions).
If you installed it — respond
anthropy is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If anthropy was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
- Kamil Mańkowski (kam193) · reporter
Detect & block this
O3 blocks anthropy-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.