lebinfmtPyPI
Advisory published Updated
lebinfmt is a confirmed malicious PyPI package (MAL-2026-10977) that steals credentials and exfiltrates sensitive data (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in lebinfmt (PyPI)
What this malware does
Analysis of lebinfmt 1.0.0 surfaced no behaviors matching supply-chain attack classes. No install-time or import-time network I/O, no credential or filesystem enumeration, no subprocess execution of fetched content, no lifecycle hooks performing sensitive actions, and no hardcoded external destinations were identified across the six files reviewed.
This package is prepared to perform steganography decoding using the same code and was published on the same day as package 'rasterkit,' later used to deliver malicious payload.
Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2026-06-textwrap-toolkit-stager
Reasons (based on the campaign):
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backdoor
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obfuscation
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crypto-related
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Downloads and executes a remote malicious script.
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exfiltration-crypto
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for lebinfmt (version 1.0.0).
If you installed it — respond
lebinfmt 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 lebinfmt 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 lebinfmt-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.