base58-corenpm
base58-core is a confirmed malicious npm package (MAL-2026-6445) that steals credentials and exfiltrates sensitive data (malicious versions 1.0.0, 1.0.1, 1.0.2…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in base58-core (npm)
What this malware does
The package advertises itself as a Base58 encoder/decoder but on require() schedules a delayed payload that performs multiple installer-side attacks. After a 72-hour activation delay, code in dist/index.cjs and dist/index.js enumerates installer-owned secret stores — MetaMask extension storage across Chrome/Chromium/Brave/Edge profiles, Telegram Desktop tdata sessions, ~/.ssh keys, ~/.npmrc _authToken values, browser profile inventories, and env/.env crypto secret variables — and POSTs the collected report to a hardcoded bare-IP endpoint at http://2.27.62.51:8080/api/health (with:8081 as backup). A setInterval clipboard monitor invokes pbpaste/xclip/PowerShell via child_process every 2.5 seconds, matches BTC/ETH/SOL address regexes plus WIF private keys, BIP39 seed phrases (12–24 words), and 64-hex private keys, rewrites detected wallet addresses to attacker-controlled destinations (bc1qjft978uykglsh0adcyx6xhkes56vqzs3fual3l, 0xd63eD44065eDb1e2ad2519B011c06412dA7B7c5B, A7ajd7W5WYdrnkeaiBRjVoK6uBEDvgnuZcpzQXqo18Ph), writes them back to the clipboard, and exfiltrates matched values and the original clipboard slice to the same endpoint. A persistence routine appends a node -e loader to ~/.bashrc, ~/.zshrc, and ~/.profile that re-invokes the payload on every shell start; on Windows it drops base58-runtime.js into the user Startup folder, keeping the clipboard hijacker and exfil active across reboots and beyond project uninstall. The 72-hour dormancy timer is designed to evade sandbox and CI dynamic analysis. The package name and keywords (bitcoin/solana/wallet/ipfs) impersonate legitimate Base58 libraries to target crypto developers.
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.
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-core (12 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging base58-core across your stack and pipelines.
If you installed it — respond
base58-core 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-core 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-core 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-core-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.