Which versions of pydefender are malicious?

The following PyPI versions of pydefender are flagged malicious: 0.0.1. Treat any of these as compromised.

How do I remediate pydefender if I installed it?

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

If pydefender 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 pydefender part of a known attack campaign?

Yes — pydefender is associated with the 2025-02-pydefender 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 pydefender across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for pydefender (version 0.0.1).

Malicious package

pydefenderPyPI

Advisory published Mar 1, 2025Updated Dec 12, 2025

pydefender is a confirmed malicious PyPI package (MAL-2025-191833) that steals credentials and exfiltrates sensitive data (malicious version 0.0.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in pydefender (PyPI)

MAL-2025-191833

Immediate action

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

pip uninstall pydefender

What this malware does

setup.py is prepared to download and run an obfuscated batch script. While the script is not detected by any AV currently, in the sandbox analysis it reveals behaviour like adding exclusions to Windows Defender

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

Campaign: 2025-02-pydefender

Reasons (based on the campaign):

Downloads and executes a remote malicious script.
malware
The package overrides the install command in setup.py to execute malicious code during installation.

Malicious versions

1 flagged

0.0.1

Indicators of compromise (SHA-256)

47fde0731c15c3a884ceb4dd40deb651eb2998414cf1eadac95c58a0f4d132bb

a1e2cc2d94eff74e302118c35c34f87e76175fe507facbe21c29883960c8223e

2df02a7ddd673cba32eb57e59dbffb385ec1c30f1c8d7e688472a17b5a18b62b

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for pydefender (version 0.0.1).
If you installed it — respond
pydefender 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 pydefender 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. pydefender on PyPI has been identified as a malicious package (version 0.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

2025-02-pydefender

References

Credits

Kamil Mańkowski (kam193)

Detect & block this

O3 blocks pydefender-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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