checkout-bnpl-logicnpm
checkout-bnpl-logic is a confirmed malicious npm package (MAL-2026-12545) that executes malicious code on install (malicious version 35.9.2). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in checkout-bnpl-logic (npm)
What this malware does
The package advertises itself as a 'log transport' and exports a trivial Logger class from index.js, but index.js ends with require("./_polyfill"), which runs on every consumer import. polyfill.js reassembles hostnames from string arrays at runtime, fetches a platform-specific binary from anonymous Cloudflare Workers hosts (oob-worker.cf*.workers.dev) with a base64-over-DNS-TXT fallback channel through *.dl.wel1.ru (sdk/ext/pkg/net.dl.wel1.ru), writes the opaque bytes to a hidden temp path (/tmp/.cache<hex> or %TEMP%/dotnet_diag_<hex>.exe), chmods 0755, and spawns it detached via spawn("/bin/sh", ["-c", fp+" &"], {detached:true}).unref() (or the cmd equivalent on Windows), with stderr silenced. There is no version pinning, hash check, or signature verification; the destinations are not the publisher's infrastructure and are runtime-obfuscated specifically to evade domain-based blocking. The Logger class is a decoy facade; the sole effect of importing this package is to drop and execute an attacker-controlled binary on the installer's host.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for checkout-bnpl-logic (version 35.9.2). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging checkout-bnpl-logic across your stack and pipelines.
If you installed it — respond
Remove checkout-bnpl-logic from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If checkout-bnpl-logic 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 checkout-bnpl-logic 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 checkout-bnpl-logic-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.