VDB
KO

MAL-2026-6428

Malicious code in leo-cron (npm)

Details

The `leo-cron` npm package was compromised as part of the Miasma worm campaign targeting the LeoPlatform npm ecosystem. On June 24, 2026, 20 LeoPlatform packages were published within a 3-second window by a threat actor who had taken over the npm account `czirker` belonging to the LeoPlatform organization.

The malicious payload is triggered automatically during `npm install` via a `binding.gyp` file using node-gyp command expansion (`<!(node index.js > /dev/null 2>&1 && echo stub.c)`), which bypasses lifecycle script scanners. The replaced `index.js` (~5.2 MB, obfuscated with ROT-N + AES-128-GCM encryption) deploys a multi-stage worm with the following capabilities:

- Credential theft: Targets npm, GitHub, PyPI, RubyGems, Kubernetes, HashiCorp Vault, AWS (IAM keys, Secrets Manager, IMDS), 1Password, JFrog Artifactory, and SSH keys. - AI tool targeting: Exfiltrates configuration files for Claude, Cursor, Gemini, and VS Code. - Worm propagation: Enumerates npm packages and auto-publishes version bumps to spread to other maintainers in the ecosystem. - GitHub persistence: Creates orphan `snapshot-<hex>` branches with fake "Dependabot Updates" workflows to maintain access after initial compromise.

Any system that installed this version should be considered fully compromised. Rotate all secrets immediately from a separate, clean machine. See the linked SafeDep report for full payload analysis, indicators of compromise, and remediation guidance.

--- _-= Per source details. Do not edit below this line.=-_

## Source: amazon-inspector (52a0b87288e27f81313e89ac69303ce3aa2dd80fde26ce278bed22c8a524ab98) binding.gyp at line 6 contains GYP command-expansion syntax (<!(...) / <!@(...) / <@(...)) inside the targets/sources fields. npm implicitly invokes node-gyp rebuild whenever a package contains a binding.gyp, and GYP evaluates command-expansion expressions as shell during the configure step — so the embedded command runs automatically on every `npm install` of this package, even though package.json declares no install/postinstall script. This is functionally equivalent to a lifecycle hook and executes attacker-chosen code on the installer's machine. The package has no apparent legitimate need for a native addon build via binding.gyp, indicating the file's only purpose is to fire the embedded shell command at install.

Are you affected?

Enter the version of the package you're using.

Affected packages

npm / leo-cron

No fixed version published yet for leo-cron (npm). Pin to a known-safe version or switch to an alternative.

References