@ecg-internal/aurora-js-formattersnpm
Advisory published Updated
@ecg-internal/aurora-js-formatters is a confirmed malicious npm package (MAL-2026-18207) that opens a backdoor for remote access (malicious versions 1.0.0, 2.0.0, 2.0.1…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @ecg-internal/aurora-js-formatters (npm)
What this malware does
The package uses an internal-looking scope (@ecg-internal) and an implausibly high version (99.0.1) consistent with dependency-confusion targeting. On install, the declared postinstall script executes beacon.cjs, which POSTs a JSON payload containing the package name, os.hostname(), __dirname install path, process.cwd(), and process.version to the hardcoded plain-HTTP bare-IP endpoint http://185.158.107.175:8787/_ah/dc. The main entry index.js additionally invokes beacon.cjs.fire() at top level on require/import, so the callback also fires when the module is loaded by a bundler or build process even if lifecycle scripts are disabled with --ignore-scripts. index.js exports a Proxy of no-op functions so consuming code and bundlers do not fail, allowing the beacon to run silently inside build pipelines. The destination IP is unrelated to any publisher infrastructure and has no TLS. The payload identifies the installing host and build environment to the operator of that endpoint, enabling enumeration of internal environments that resolved this scoped name from the public registry.
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.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for @ecg-internal/aurora-js-formatters (5 malicious versions).
If you installed it — respond
@ecg-internal/aurora-js-formatters establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If @ecg-internal/aurora-js-formatters 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
Detect & block this
O3 blocks @ecg-internal/aurora-js-formatters-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.