MAL-2026-11784 Malicious code in @qlik/browserslist-config (npm)

npm/@qlik/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.

Package advertises itself as a static browserslist configuration under the @qlik/ scope but declares preinstall: node setup.mjs in package.json. setup.mjs is obfuscated (_0x... identifiers) and downloads a Bun runtime binary from github.com/oven-sh/bun releases, extracts it to a temp directory, chmods it executable, and invokes it via execFileSync against the sibling math_init.js. math_init.js is a 727KB single-line file containing a shuffled string-array plus rotation decoder (obfuscator.io shape) and is not referenced by the advertised index.js entry, which merely exports a browserslist array. The tarball's files field declares only index.js, yet setup.mjs and math_init.js are shipped alongside it. Purpose mismatch (a browserslist config has no legitimate need for a second runtime or a 727KB obfuscated bundle), scope impersonation of Qlik, undeclared tarball contents, and install-time execution of an obfuscated blob under an alternate runtime together match the alternate-runtime-dropper pattern.

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.