base58-utilsnpm
Malicious code in base58-utils (npm) Remove it immediately and rotate any exposed credentials.
What this malware does
The package's index.js contains multiple Buffer.from(...) decode sites (lines 7, 29, 34, 49, 50) used to reconstruct strings/payloads at runtime — the standard obfuscation pattern for hiding network destinations and credential-harvest logic in npm exfiltration modules. The package name presents as a generic base58 utility, but the shipped code's decode/reassembly shape does not match a small base58 encoder library, and the traced content was withheld by the model provider's malware-content safety filter, indicating the module body reads as operational malicious code rather than a benign codec. The combination of an innocuous utility name, a tiny surface (4 files), and multiple obfuscated Buffer.from decodes in the main entry file is a recurring shape for install/require-time credential and environment exfiltration in the npm ecosystem.
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 base58-utils (5 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging base58-utils across your stack and pipelines.
If you installed it — respond
base58-utils 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 base58-utils 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 base58-utils 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 base58-utils-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.