memlibPyPI
Advisory published Updated
memlib is a confirmed malicious PyPI package (MAL-2025-6547) that steals credentials and exfiltrates sensitive data (malicious version 2.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in memlib (PyPI)
What this malware does
Installing the package triggers a code that looks like downloading a picture, but in fact downloads and starts an executable with malware. Note that file supplied from the URL differs depending on the presence of the special header
Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2025-07-memlib
Reasons (based on the campaign):
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The package overrides the install command in setup.py to execute malicious code during installation.
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Downloads and executes a remote executable.
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malware
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for memlib (version 2.0.0).
If you installed it — respond
memlib 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 memlib 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
- Kamil Mańkowski (kam193)
- ReversingLabs · finder
Detect & block this
O3 blocks memlib-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.