MAL-2026-4486 Malicious code in atomic-notes (npm)

package.json declares preinstall:./.github/scripts/precheck, which executes a 976 KB stripped, UPX-packed Linux x86_64 ELF shipped at .github/scripts/precheck on every npm install. The binary is opaque (packed + stripped, UPX marker http://upx.sf.net present) and contains kernel/syscall surface (LIBBPF, PTRACE, NETLINK, NETLINK_DIAG), a TLS/HTTP client (HTTP/1.1, Ed25519, RSA_PKCS1_, POST), and references to USERPROFILE and https:// — capabilities entirely unrelated to the package's advertised purpose as a JavaScript Arweave/AO 'atomic-notes' library. The binary is hidden under .github/scripts/, a directory normally reserved for CI workflow YAML, not runtime code. Author and description fields in package.json are empty placeholders. There is no hash verification, no documentation, and no legitimate reason for a JS library to execute an opaque privileged Linux binary at install time.

This package was compromised as part of the IronWorm campaign. This campaign executes a malicious binary payload during installation via a preinstall hook. The payload is a Rust-built infostealer that targets developer environments, scanning for and harvesting credentials related to cloud providers, object storage, databases, source-control, package registries, and AI developer tools. It also targets cryptocurrency wallets, specifically injecting a malicious JavaScript hook into the Exodus desktop wallet to capture passwords and recovery phrases. Furthermore, the malware exhibits worm-like behavior by stealing GitHub and NPM credentials to push malicious updates to the victim's repositories and publish trojanized packages, and it uses an eBPF-based kernel rootkit to hide its processes and network connections on Linux systems.