Which versions of libtasnl are malicious?

The following PyPI versions of libtasnl are flagged malicious: 1337.0.0. Treat any of these as compromised.

How do I remediate libtasnl if I installed it?

libtasnl 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 libtasnl — how do I know if it already compromised me?

If libtasnl 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 libtasnl part of a known attack campaign?

Yes — libtasnl is associated with the RLMA-2025-05617, GENERIC-questionable-pentest, RLUA-2026-00473 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 libtasnl across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for libtasnl (version 1337.0.0).

Malicious package

libtasnlPyPI

Advisory published Oct 22, 2025Updated Mar 19, 2026

libtasnl is a confirmed malicious PyPI package (MAL-2025-191645) that steals credentials and exfiltrates sensitive data (malicious version 1337.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in libtasnl (PyPI)

MAL-2025-191645

Immediate action

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

pip uninstall libtasnl

What this malware does

Generic campaign for all (likely) research / pentests, where the amount or art of collected data raises questions about the privacy, security and ethical side.

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

Campaign: GENERIC-questionable-pentest

Reasons (based on the campaign):

exfiltration-env-variables
exfiltration-generic
The package overrides the install command in setup.py to execute malicious code during installation.
typosquatting

Malicious versions

1 flagged

1337.0.0

Indicators of compromise (SHA-256)

8989214aa2d7a1235632c53b0687389dd88b8a52d4a23019650c9fea9eb3d3f1

b50880a5309c35fe5630fe38e39600cceb622b1a69e28191b9653baac29da09b

0da2df30cd680f292df7b195f51829e4afc94604336223d58b0bfca92714d9fc

8489f165dd9360f9b9535bb908a6831c2ab05d453a66b3dcd889f7796fd6e377

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for libtasnl (version 1337.0.0).
If you installed it — respond
libtasnl 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 libtasnl 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. libtasnl on PyPI has been identified as a malicious package (version 1337.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2025-05617GENERIC-questionable-pentestRLUA-2026-00473

References

bad-packages.kam193.eu

Credits

Kamil Mańkowski (kam193)
ReversingLabs · finder

Detect & block this

O3 blocks libtasnl-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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