🛡️ MAL-2026-11991 — verdaccio-tarball-local-storage

Malicious code in verdaccio-tarball-local-storage (npm)

npm/verdaccio-tarball-local-storage is affected by the large-scale, self-propagating npm supply-chain worm of 2026-08-04 (the "Shai-Hulud: Here We Go Again" wave) — the same campaign that began with the compromise of the keyv and cacheable maintainer account. The listed version(s) were trojanized and republished by the worm after it reached an npm publish token belonging to a maintainer in this namespace; the payload enumerates every package a stolen token controls and republishes each with the same hook, so many packages under this scope were poisoned in the same short window. Every poisoned release adds a preinstall hook ("preinstall": "node setup.mjs") that runs on a bare npm install, before any project code. setup.mjs downloads a standalone Bun runtime and runs a byte-identical, heavily obfuscated ~728 KB second-stage credential stealer (shipped as Math_Symbol.js / math_init.js). It harvests GitHub, npm, AWS, GCP, Azure, HashiCorp Vault and Kubernetes credentials plus generic secrets and private keys (TruffleHog-style sweep), reads CI/CD secrets and identifies build runners, then republishes further packages the stolen token can reach. Rather than a fixed command-and-control host, it exfiltrates stolen findings to attacker-created GitHub repositories (descriptions reading "Shai-Hulud: Here We Go Again") and over DNS. Treat any environment that installed an affected version (with install scripts enabled) as compromised: rotate and revoke all reachable credentials (npm and GitHub tokens, cloud keys, Vault/Kubernetes secrets, and CI org/repo secrets). Part of the August 2026 npm worm that poisoned 400+ packages across many organizations.

Source: amazon-inspector

The npm package's preinstall hook runs node setup.mjs, which prefers a system bun binary and otherwise downloads a Bun runtime archive from a GitHub releases URL constructed at runtime, unpacks it to a temp directory, chmods the extracted binary 0o755, and invokes it against the sibling file math_init.js via execFileSync. math_init.js is a 727 KB single-line, heavily obfuscated JavaScript blob (character-array rotator plus a large custom Base64-style alphabet constant, matching the obfuscator.io shape) that is never referenced by the plugin's advertised entry (dist/index.js) and is only reachable through the freshly downloaded Bun runtime. The package name verdaccio-tarball-local-storage closely resembles the legitimate @verdaccio/local-storage, and the benign-looking dist/index.js presents a plausible Verdaccio-plugin cover while the actual install-time behavior is an alternate-runtime dropper that executes an opaque bundled payload on npm install. This is the alternate-runtime-dropper fingerprint: a second language runtime is fetched at install specifically to execute a bundled obfuscated blob outside the Node-based execution path that most scanners inspect.

Source: ghsa-malware

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.