MAL-2026-6672

ulid-xyz is a typosquat of the popular ulid library (sortable unique IDs) and is a cross-platform Remote Access Trojan delivered via a postinstall hook. The package.json postinstall superficially looks like an inline `node -e` guard that checks for the existence of a dist file, but it actually launches dist/node/utils.js as a detached background process, which in turn runs dist/node/payload.js -- a 467 KB bundled RAT. payload.js decodes XOR+base64-obfuscated configuration (_CFG.WS / _CFG.HTTP) to beacon to a hardcoded attacker-controlled C2 over WebSocket at ws://95.216.232.162:8010/ (with an HTTP fallback at http://95.216.232.162:8010/), establishing a WebSocket RAT channel. It installs persistence on all three major operating systems under the stem MicrosoftSystem64: on Windows under %LOCALAPPDATA%\MicrosoftSystem64; on macOS under ~/Library/Application Support/MicrosoftSystem64 plus a LaunchAgent at ~/Library/LaunchAgents/com.launchkeeper.MicrosoftSystem64.plist; and on Linux under ~/.local/share/MicrosoftSystem64. The install-time detached spawn (process management capability) and the ~8x package size spike (64 KB to 536 KB) correspond to the bundled RAT payload -- behavior a ULID library has no legitimate need for. All versions of ulid-xyz were published by the same actor (iloiyxo643 / iloiyxo643@ufiwi.space, a disposable email address) and are considered malicious.

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## Source: amazon-inspector (23041702700830f3caa094b14bf923ac78f81d6d0cef96ec784e948dbe4fc705) Package publishes as 'ulid-xyz' — a name edit away from the established 'ulidx' / 'ulid' libraries — and its README instructs users to `npm install index-ulid` and `import { ulid } from "index-ulid"`, pointing at a second confusable name maintained by the same author. The declared homepage links to the canonical ulid repository (github.com/ulid/javascript), reinforcing the impersonation. package.json declares `scripts.postinstall` that runs `node dist/node/utils.js` after a required-files guard, but `dist/node/utils.js` is absent from this tarball — only `dist/node/index.cjs` and `dist/node/index.js` ship. As published, the guard throws and the postinstall is inert, so no malicious code executes on install in this version. The wired-but-missing lifecycle target combined with the confusable name and a bloated runtime dependency list (pino, ws, zod, esbuild, tsup, ts-node, typescript, @types/node, @types/ws, and a meta `postinstall` package — none required for ULID generation, where the legitimate ulidx ships zero runtime deps) is consistent with a dormant-dropper staging pattern: ship a benign tarball under a confusable name, then publish a future version that fills in the postinstall target. No exfiltration, no install-time RCE, and no silent-relay are present in the current code, so a public block would overclaim the present-version harm. Routing to human review for confusion-risk assessment and so a reviewer can monitor future versions of this name.

## Source: ghsa-malware (145986a950881e6fcf9c8e4c76dbb633b8ffa46de560e864c9ff6bb15d40adf6) 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.