Which versions of utf-cleaner are malicious?

The following PyPI versions of utf-cleaner are flagged malicious: 3.3.7, 3.3.8, 3.3.9, 3.4.0, 3.4.1, 3.4.2. Treat any of these as compromised.

How do I remediate utf-cleaner if I installed it?

utf-cleaner 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 utf-cleaner — how do I know if it already compromised me?

If utf-cleaner 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 utf-cleaner part of a known attack campaign?

Yes — utf-cleaner is associated with the 2026-03-old-utf-cleaner 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 utf-cleaner across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for utf-cleaner (6 malicious versions).

Malicious package

utf-cleanerPyPI

Advisory published Jan 10, 2025Updated Mar 23, 2026

utf-cleaner is a confirmed malicious PyPI package (MAL-2025-73) that steals credentials and exfiltrates sensitive data (malicious versions 3.3.7, 3.3.8, 3.3.9…). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in utf-cleaner (PyPI)

MAL-2025-73

Immediate action

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

pip uninstall utf-cleaner

What this malware does

During import, the package silently downloads and executes remote code. This code starts a web server in the separate process and listens for commands to execute from a C2 server, as well as periodically sends a beacon to C2 allowing discovery and finishing execution.

This package is closely related to Github repository https://github.com/xcummins/tg-outline-seller/ from the same author, where it's used as dependency effectively compromising its users.

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

Campaign: 2026-03-old-utf-cleaner

Reasons (based on the campaign):

Downloads and executes a remote malicious script.
The package contains code to execute remote commands (probably limited to a specific set) on the victim's machine.

The OpenSSF Package Analysis project identified 'utf-cleaner' @ 3.4.1 (pypi) as malicious.

It is considered malicious because:

The package executes one or more commands associated with malicious behavior.

Malicious versions

6 flagged

3.3.73.3.83.3.93.4.03.4.13.4.2

Indicators of compromise (SHA-256)

2f3468ce127ee2c3a221f8b2331c633be1c43772101c4baeca6ab4e47710b9ac

6ee317562a7c07ecbbc119802e7f69e0ae70d1876cb9c72a5c94b6316064ba2f

a0133dbcab387829b4229c7da1b6cb02390e11faf82ea682a1f1d0d649d2c2d6

c87e8af9d44b22afadb4888905252edf4ec91532c1ffcd7fce378268a99ae4bf

8382837e2b4420621b1ac738092bf8d584dde848e0f8cd6bbf73b0fbc6f74fcb

09b9e5c5deafbf756df5201976fdbdc3c61c10e815234df9aeb32764a3cd9652

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for utf-cleaner (6 malicious versions).
If you installed it — respond
utf-cleaner 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 utf-cleaner 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. utf-cleaner on PyPI has been identified as a malicious package (versions 3.3.7, 3.3.8, 3.3.9, 3.4.0, 3.4.1, 3.4.2 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

2026-03-old-utf-cleaner

References

Credits

Kamil Mańkowski (kam193) · reporter
OpenSSF: Package Analysis · finder

Detect & block this

O3 blocks utf-cleaner-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

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