pymaasPyPI
Advisory published Updated
pymaas is a confirmed malicious PyPI package (MAL-2026-15929) that steals credentials and exfiltrates sensitive data (malicious version 99.99.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in pymaas (PyPI)
What this malware does
On import pymaas, top-level code in the package invokes a _canary() function that collects the entire os.environ dictionary and socket.gethostname(), serializes them as JSON, and POSTs the payload via urllib.request.urlopen to the hardcoded host https://vuorblucjega.dssldrf.net/python-install-log/pymaas. The behavior runs unconditionally on import with no consent, no gating, and no relationship to the destination domain. Combined with the implausibly high version 99.99.0 and the package's own dependency confusion test description, the shipped code is a dependency-confusion beacon that harvests any credentials present in the process environment (CI tokens, cloud provider keys, registry auth tokens, database passwords) and delivers them to an external non-publisher host.
During import, the package exfiltrates environment variables.
Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2026-09-amirgo4496
Reasons (based on the campaign):
-
exfiltration-env-variables
-
dependency-confusion
-
The package contains code to exfiltrate basic data from the system, like IP or username. It has a limited risk.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for pymaas (version 99.99.0).
If you installed it — respond
pymaas 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 pymaas 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 pymaas-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.