psbt-utilsPyPI
psbt-utils is a confirmed malicious PyPI package (MAL-2026-11520) that steals credentials and exfiltrates sensitive data (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in psbt-utils (PyPI)
What this malware does
psbt-utils presents itself as a PSBT/Bitcoin wallet signing library handling WIF and hex private keys. update.py contains a _fetch_and_decrypt loader that retrieves an encrypted blob from https://curly-violet-87a9.ricardorichp.workers.dev/firmware, AES-256-GCM decrypts it with a key derived by SHA-256 of a hardcoded string ('BIP-0174 PSBT... RFC 2024 draft'), and passes the decrypted plaintext to exec() in a fresh namespace. The exec'd code defines TelemetrySender.load and TelemetrySender.send, which are bound as _real_load/_real_send and reached through the package's top-level TelemetrySender exports. Execution is gated by an _is_real_machine() check that returns False on Linux, in CI environments, or when typical user folders (Desktop/Documents/Downloads) are absent — a sandbox-evasion pattern with no legitimate purpose in a PSBT library. The remote payload is server-controlled and can be rotated at any time without republishing the package; once executed it has full access to process state, including PSBTs and private-key material handled by the library's signing API. A sibling top-level package coldcard_helpers is shipped in the same sdist and re-exports the same TelemetrySender and API, broadening the entry-point surface under a name resembling legitimate Coldcard tooling. The combination of a wallet/signing package, hidden fetch-decrypt-exec of encrypted remote code from a non-publisher Cloudflare Workers subdomain, sandbox-evasion gating, and dual entry-point names is a wallet-secret exfiltration dropper.
The code advertised as a firmware upgrader for hardware wallets in fact downloads an infostealer. The stealer searches the machine for cryptocurrency sensitive data (wallet files, seeds), browser data (passwords, cookies), all kinds of credentials (including tokens, passwords, SSH keys, TOTP seeds etc.), other sensitive files and current clipboard content. Data are exfiltrated, and the stealer configures persistence via scheduled tasks or LaunchAgent. The code deliberatly doesn't start in CI environments and checks if the system looks real.
Continuation of 2026-08-coldcard-helpers campaign. Related packages are used in malicious repository https://github.com/domaup/coldcard-poc
Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2026-08-psbt-utils
Reasons (based on the campaign):
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infostealer
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files-exfiltration
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clipboard-stealing
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exfiltration-ssh-keys
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obfuscation
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crypto-related
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exfiltration-cloud-tokens
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Downloads and executes a remote malicious script.
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exfiltration-browser-data
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exfiltration-crypto
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exfiltration-credentials
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persistence
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 psbt-utils (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging psbt-utils across your stack and pipelines.
If you installed it — respond
psbt-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 psbt-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 psbt-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
- Kamil Mańkowski (kam193) · reporter
Detect & block this
O3 blocks psbt-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.