MAL-2026-11743

Dashboard / Malicious Package / MAL-2026-11743

MAL-2026-11743

Summary: Malicious code in @ornikar/browserslist-config (npm)

Details: npm/@ornikar/browserslist-config 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 (1ae69f4eb48f0147d86c7ce81481d520e709182b702e9c07bde3ddc6a3f3c988) The package's advertised purpose is a static browserslist configuration (degraded-support.js exports a one-line array). Its package.json declares a preinstall hook `node setup.mjs` that runs automatically on `npm install`. setup.mjs is written with obfuscator.io-style renaming and per-function string dictionaries (`_0xNNNN` variable names, indirected literals such as `--version`, `musl`, `/etc/os-release`, `Alpine`, and the download host) to hide its logic. It constructs a URL of the form `https://github.com/oven-sh/bun/releases/download/bun-v<version>/<arch>.zip`, downloads and extracts the Bun runtime into a temp directory, marks it executable, and invokes it via `execFileSync(bunPath, [join(D, 'math_init.js')], {cwd: D})` against a locally-shipped 728KB bundle. `math_init.js` is a Bun-compiled artifact (`// @bun @bun-cjs`) containing a ~4000-entry numeric/string constants array `n7gIxM` and a rotator function `WV8StW` that permutes it at runtime — a canonical string-array obfuscation shape used to conceal endpoints, credentials, and behavior. A browserslist configuration has no functional need for an alternate JavaScript runtime or a large opaque bundle, and the choice to fetch Bun specifically causes the payload to bypass Node-focused install-time scanners. The combination of obfuscated preinstall logic, an alternate-runtime fetch from outside the ecosystem's normal install path, and auto-execution of an opaque local bundle constitutes install-time remote code execution on the installer's machine, with the executed payload's behavior deliberately hidden from static review. Source: ghsa-malware (e3447b4a08116debde2221ae77237c1a5eca8b077ff9040d0d4382da5e611b23) 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.

References: https://socket.dev/blog/popular-npm-packages-in-the-keyv-and-cacheable-namespaces-compromised-in-active-supply-chain, https://www.aikido.dev/blog/keyv-and-friends-compromised-in-npm-supply-chain-attack, https://safedep.io/keyv-npm-supply-chain-compromise/, https://www.npmjs.com/package/@ornikar/browserslist-config, https://github.com/advisories/GHSA-vw7j-698w-fqgm, https://www.npmjs.com/package/@ornikar/browserslist-config/v/8.0.10, https://www.npmjs.com/package/@ornikar/browserslist-config/v/8.0.9, https://www.npmjs.com/package/@ornikar/browserslist-config/v/8.0.8, https://www.npmjs.com/package/@ornikar/browserslist-config/v/8.0.7, https://www.npmjs.com/package/@ornikar/browserslist-config/v/8.0.6, https://www.npmjs.com/package/@ornikar/browserslist-config/v/8.0.4, https://www.npmjs.com/package/@ornikar/browserslist-config/v/8.0.3, https://www.npmjs.com/package/@ornikar/browserslist-config/v/8.0.5