Which versions of mnemoniclib are malicious?

The following PyPI versions of mnemoniclib are flagged malicious: 0.20.1, 0.21.1, 0.22.1. Treat any of these as compromised.

How do I remediate mnemoniclib if I installed it?

mnemoniclib 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.

I already installed mnemoniclib — how do I know if it already compromised me?

If mnemoniclib 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.

Is mnemoniclib part of a known attack campaign?

Yes — mnemoniclib is associated with the 2026-03-mnemoniclib campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find mnemoniclib across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for mnemoniclib (3 malicious versions).

Malicious package

mnemoniclibPyPI

Advisory published Mar 30, 2026Updated Mar 30, 2026

mnemoniclib is a confirmed malicious PyPI package (MAL-2026-2299) that steals credentials and exfiltrates sensitive data (malicious versions 0.20.1, 0.21.1, 0.22.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in mnemoniclib (PyPI)

MAL-2026-2299

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

pip uninstall mnemoniclib

What this malware does

Clone of a legitimate library with added malicious code that runs during generating a new mnemonic. The malicious code collects data related to cryptocurrency wallets and selected other files, and exfiltrate them to a hardcoded location.

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

Campaign: 2026-03-mnemoniclib

Reasons (based on the campaign):

clones-real-package
action-hidden-in-lib-usage
crypto-related
exfiltration-crypto
files-exfiltration

Malicious versions

3 flagged

0.20.10.21.10.22.1

Indicators of compromise (SHA-256)

c88fa4e30e2437fef5f03db434adb0f34ee48d8bec2d3361d123b10086b28772

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for mnemoniclib (3 malicious versions).
If you installed it — respond
mnemoniclib 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 mnemoniclib 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

No. mnemoniclib on PyPI has been identified as a malicious package (versions 0.20.1, 0.21.1, 0.22.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

2026-03-mnemoniclib

References

bad-packages.kam193.eu

Credits

Kamil Mańkowski (kam193) · reporter

Detect & block this

O3 blocks mnemoniclib-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

Explore

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