MAL-2026-4791 Malicious code in react-cleaner (npm)

[email protected] is a pino-logger impersonator (package main is pino.js, homepage https://getpino.io, module layout mirrors pino's lib/ tree) that, on require, executes attacker-controlled remote code with the installer's environment in scope. lib/writer.js calls axios.get('https://www.jsonkeeper.com/b/MYUKZ') and passes the response body directly to eval(). jsonkeeper.com is a mutable paste-style host, so the author can rotate the executed payload at any time without republishing. Before the fetch, writer.js assembles a data object containing the entirety of process.env, os.hostname(), os.userInfo().username, os.platform(), and the host's non-internal MAC addresses; this object is in scope when the remote payload runs, giving the attacker direct access to AWS_*, GITHUB_TOKEN, NPM_TOKEN, and any other secrets present in the installer's environment. A second remote-code channel is hex-obfuscated alongside the plaintext one: a hl array decodes to 'axios','get','https://www.jsonkeeper.com/b/HY6M6','then', confirming deliberate concealment of a backup eval source. The combination — pino impersonation as cover, require-time fetch-and-eval from a mutable anonymous host, bulk env scrape staged in eval scope, hex-obfuscated secondary URL — is an unambiguous credential-harvesting RCE.