Which versions of num2words are malicious?

The following PyPI versions of num2words are flagged malicious: 0.5.15, 0.5.16. Treat any of these as compromised.

How do I remediate num2words if I installed it?

Remove num2words from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.

I already installed num2words — how do I know if it already compromised me?

If num2words was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.

Is num2words part of a known attack campaign?

Yes — num2words is associated with the GHSA-jxr6-qrxx-2ph2 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 num2words across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for num2words (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging num2words across your stack and pipelines.

Malicious package

num2wordsPyPI

num2words is a confirmed malicious PyPI package (MAL-2025-6794) that executes malicious code on install (malicious versions 0.5.15, 0.5.16). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in num2words (PyPI)

MAL-2025-6794

Immediate action

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

pip uninstall num2words

What this malware does

The num2words project was compromised via a phishing attack and two new versions were uploaded to PyPI containing malicious code. The affected versions have been removed from PyPI, and users are advised to remove the affected versions from their environments.

The num2words project was compromised via a phishing attack and two new versions were uploaded to PyPI containing malicious code.

Malicious versions

2 flagged

0.5.150.5.16

Indicators of compromise (SHA-256)

36822c42f7e862f29cef9734efec9a9a9cc44a80e619e954dd25c12239d15767

23a528edd10eb63e7c7932830fdb314983cadc840ce8ccfbaa04ad821bbdc1da

Detection & response playbook

Malicious package

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for num2words (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging num2words across your stack and pipelines.
If you installed it — respond
Remove num2words from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If num2words was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks num2words before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.

Frequently asked questions

No. num2words on PyPI has been identified as a malicious package (versions 0.5.15, 0.5.16 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

GHSA-jxr6-qrxx-2ph2

References

Detect & block this

O3 blocks num2words-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring

Explore

All malware advisories How O3 detects malware Vulnerability database