Which versions of obfuscation are malicious?

The following PyPI versions of obfuscation are flagged malicious: 3.23.0, 3.23.2, 3.23.3. Treat any of these as compromised.

How do I remediate obfuscation if I installed it?

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

If obfuscation 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 obfuscation part of a known attack campaign?

Yes — obfuscation is associated with the 2026-05-cryptolock 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 obfuscation across my projects, lockfiles, and CI pipelines?

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

Malicious package

obfuscationPyPI

Advisory published May 31, 2026Updated May 31, 2026

obfuscation is a confirmed malicious PyPI package (MAL-2026-5100) that steals credentials and exfiltrates sensitive data (malicious versions 3.23.0, 3.23.2, 3.23.3). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in obfuscation (PyPI)

MAL-2026-5100

Immediate action

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

pip uninstall obfuscation

What this malware does

During installation, the code tamper with security settings and downloads and executes malicious executable.

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

Campaign: 2026-05-cryptolock

Reasons (based on the campaign):

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

Malicious versions

3 flagged

3.23.03.23.23.23.3

Indicators of compromise (SHA-256)

9a6d747918a89b433d6b670595d6b8d3049f49a69762c3e483d4f0f9dbeb81a3

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for obfuscation (3 malicious versions).
If you installed it — respond
obfuscation 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 obfuscation 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. obfuscation on PyPI has been identified as a malicious package (versions 3.23.0, 3.23.2, 3.23.3 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

2026-05-cryptolock

References

Credits

Kamil Mańkowski (kam193) · reporter

Detect & block this

O3 blocks obfuscation-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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