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CRITICAL npm Malware

Malicious code in node-fsagent (npm)

MAL-2026-10506 · GHSA-qgvj-fw22-j5v6

Published · Modified

Description


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Source: amazon-inspector (a3a0392a3ddea9b6099e8501fdb827f586a410323cecea214aa50fc1be42183b)

The package tarball ships archive-sender.js, which archives the host path /root/.codex, splits the tar into ~200MB chunks, reconstructs an npm registry _authToken at runtime by XOR-ing an embedded byte array against a key array, writes that token into the local npm config via npm config set //registry.npmjs.org/:_authToken, and then invokes npm publish --access public on each chunk as sequential versioned releases of the package name 'node-fsagent'. This uses the public npm registry as a covert data-exfiltration channel and simultaneously constitutes credential distribution: the embedded token grants publish rights to the token owner's npm account and would allow republishing over the 'node-fsagent' name (and any other packages owned by that account). The declared main entry (index.js) is a single newline and no lifecycle scripts are declared in package.json, so archive-sender.js does not auto-execute on npm install or on require('node-fsagent'); the malicious behavior fires only when the script is invoked directly. The package advertises no legitimate functionality (empty main, no documented API), and the shipped script's only purpose is host-path archival and registry-token-driven upload.

Source: ghsa-malware (f92683bc191915cf41dfbd19408918115b320288317469de7b00014e4c3fec34)

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

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