MAL-2026-11133 Malicious code in chain-analyze (npm)
- Package
- chain-analyze
- Registry
- npm
What is MAL-2026-11133?
MAL-2026-11133 is a malicious package in chain-analyze, published on 28 Jul 2026.
Official description
The published tarball's dist bundles (dist/sigchain-js.cjs.js, dist/sigchain-js.esm.js, dist/sigchain-js.umd.js) execute at module load: they read an encrypted blob from the sibling dependency 'chain-manager' (either imported as desKey or read from a file under node_modules/chain-manager via fs.readFileSync), DES-decrypt it with a hardcoded PASSWORD, then invoke child_process.spawn('node', [], { detached: true,… }) and pipe the decrypted script into the child's stdin — running attacker-controlled Node.js code on the installer's machine on any require()/import of the package. The dropper code is present only in dist/; the src/ tree contains no reference to 'chain-manager' or to spawn('node'), and package.json's declared main 'dist/chain-analyze.cjs.js' is not shipped — only the tampered dist/sigchain-js.* bundles are, so consumers resolve to the malicious build while source reviewers see a clean Theta blockchain SDK. package.json declares author 'Theta Labs' and describes itself as a JavaScript library for the Theta blockchain, impersonating the official @thetalabs/theta-js SDK, and pins 'chain-manager' ^1.0.9 which supplies the encrypted payload — a split-package design that hides the executable code from scanners inspecting only this tarball.
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.
What should I do about MAL-2026-11133?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.
Sources
Also known as GHSA-vmj5-cm6w-jrgj.