proxycerPyPI
Advisory published Updated
proxycer is a confirmed malicious PyPI package (MAL-2026-15935) that steals credentials and exfiltrates sensitive data (malicious version 0.1.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in proxycer (PyPI)
What this malware does
The package's top-level init.py imports starts.py, which is a single-line loader that reverses a ~100KB string literal, base64-decodes it, marshal.loads the result into a code object, and exec()s it. All actual functionality is concealed behind reversal + base64 + marshal bytecode obfuscation, with an empty README and empty PKG-INFO description. The obfuscated code object runs automatically on import proxycer, so any behavior it contains (credential access, outbound network, filesystem writes, persistence) executes on the installer's host without source visibility.
The provided functionality hides code that exfiltrates files to a remote location.
Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2026-09-asti
Reasons (based on the campaign):
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files-exfiltration
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action-hidden-in-lib-usage
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target:android
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for proxycer (version 0.1.0).
If you installed it — respond
proxycer 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 proxycer 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
Campaign
References
Credits
- Amazon Inspector · finder
- Kamil Mańkowski (kam193) · reporter
Detect & block this
O3 blocks proxycer-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.