MAL-2026-6098 Malicious code in stackus (npm)

On require(), lib/writer.js (loaded transitively from the package's main pino.js) collects the installer's full process.env together with host identifiers (os.hostname, os.userInfo().username, os.platform(), and external MAC addresses) into a data object, then performs an unconditional axios GET to https://www.jsonkeeper.com/b/MYUKZ and passes the response body through eval(). A second hex-obfuscated jsonkeeper.com URL (https://www.jsonkeeper.com/b/HY6M6) is also staged in the same file. jsonkeeper.com is an anonymous, user-editable JSON paste host, so the eval'd payload is mutable attacker-controlled content with closure access to the staged environment dump — a complete credential-exfiltration + remote-code-execution channel that fires on every consumer that imports the package. The package masquerades as the pino logger: it declares main=pino.js, homepage=https://getpino.io, replicates pino's writer/proto/levels/transport API surface, and ships pino-branded images, while the package name 'stackus' is unrelated to pino.

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.