polyutilPyPI
Malicious code in polyutil (PyPI) Remove it immediately and rotate any exposed credentials.
What this malware does
The package is prepared to download a hardcoded executable and save it in %LOCALAPPDATA% under a very generic name, clearly aiming to hide its existence. Code is also prepared to alter MarkOfTheWeb, start as admin and run the executable, but in analyzed versions this behavior was not triggered in any existing code path. The downloading will happen e.g. on starting the declared command line.
Remote executables are standalone applications or installators, including ClickOnce installators. However, in the analysis attempts, none of them showed clear malicious behavior, in most cases crashing during the analysis. Captured network traffic shows communication with the remote server and likely expects the URL of the next stage, which was not delivered from the server. Additionally, the code embeds a separate path for execution on non-Windows machines. It attempts to execute a remote script, but in analyzed versions, the domain used is already suspended and not reachable.
In newer packages the remote code is another downloader, which then downloads a PyInstaller-packed executable that just calls back home but has no more functionality.
Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2026-02-magichat
Reasons (based on the campaign):
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Downloads and executes a remote executable.
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other
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typosquatting
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for polyutil (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging polyutil across your stack and pipelines.
If you installed it — respond
polyutil 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 polyutil 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 polyutil 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
Campaign
References
Credits
- Kamil Mańkowski (kam193) · reporter
Detect & block this
O3 blocks polyutil-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.