{"answers":{"affected":"1 open source package ship an affected version, including multicore-kit.","exploited":"There is no known exploitation of MAL-2026-15995 in the wild and no public exploit code.","fix":"Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.","what":"MAL-2026-15995 is a malicious package in multicore-kit, published on 6 Sep 2026."},"fix_prompt":"MAL-2026-15995 is a malicious package: multicore-kit (npm). Every version was published to cause harm.\n\nTask:\n1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.\n2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.\n3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.\n4. If the package is not used anywhere, say so and change nothing.\n\nReference: https://insights.sbomify.com/MAL-2026-15995/ (Markdown: https://insights.sbomify.com/MAL-2026-15995/index.md)","id":"MAL-2026-15995","markdown":"https://insights.sbomify.com/MAL-2026-15995/index.md","name":"MAL-2026-15995","record":{"aliases":["GHSA-q588-cfvg-8346"],"analysis":null,"analysis_generated_by":null,"assigner":null,"cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"multicore-kit@1.1.5 is published under a spoofed author identity (Blake Embrey, maintainer of array-flatten) and advertises itself as an array utility, but multicore-kit.js contains a heavily obfuscated top-level IIFE that fires on require(). On import it creates ~/.vs_cache, writes an obfuscated JavaScript payload plus a synthesized package.json declaring axios, better-sqlite3, node-machine-id, and socket.io-client (with @primno/dpapi and sudo-prompt added on Windows), spawns `npm install` inside that staging directory, and then executes the decoded payload with node (or via powershell.exe on Windows). The Windows dependency set (@primno/dpapi to unwrap the Chrome/Edge Local State DPAPI key, better-sqlite3 to read the Login Data SQLite databases, socket.io-client for a C2 channel, node-machine-id for host fingerprinting, sudo-prompt for privilege escalation) is the standard toolkit of a browser-credential stealer and is unrelated to any array-flatten functionality. The main module uses obfuscator.io-style string-array rotation with a base64+URI decoder, and the on-disk payload embeds a second layer of the same obfuscation.\n\nAny 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.","ecosystems":["npm"],"exploits":{"exploitdb":null,"first_seen":null,"github_poc":null,"max_poc_stars":null,"metasploit":null,"nuclei":null,"refs":[],"tier":null},"has_fix":false,"headline":"Malicious code in multicore-kit (npm)","id":"MAL-2026-15995","indexable":true,"kev":null,"kind":"malicious","links":{"ecosystem":"npm","product":null,"products":[],"type":null,"year":"2026"},"n_packages":1,"n_references":null,"packages":[{"ecosystem":"npm","fixed":[],"introduced":["0"],"last_affected":[],"package":"multicore-kit","purl":"pkg:npm/multicore-kit","source":"MAL-2026-15995"}],"products":null,"published":"2026-09-06","related":[],"sources":[{"class":"attribution","licence":"Apache-2.0","name":"OpenSSF Malicious Packages","prefix":"MAL"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":null,"updated":null,"vendors":null},"summary":null,"url":"https://insights.sbomify.com/MAL-2026-15995/"}