bnpl-blocks-desktop-bnpl-button-setnpm
Advisory published Updated
bnpl-blocks-desktop-bnpl-button-set is a confirmed malicious npm package (MAL-2026-12915) that executes malicious code on install (malicious version 35.3.7). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in bnpl-blocks-desktop-bnpl-button-set (npm)
What this malware does
On require of the package, index.js loads polyfill.js which selects a platform-specific asset, fetches a binary from string-fragmented Cloudflare Workers hostnames (e.g. oob-worker.cf102-baf.workers.dev, assembled at runtime via array.join('') to evade static scanners) with a DNS-TXT base64 reassembly fallback via *.dl.wel1.ru, writes the payload to /tmp or %TEMP% under disguised names such as '.cache<rand>' or 'dotnet_diag_<rand>.exe', chmods it 0755, and spawns it detached via /bin/sh -c '<path> &' (or cmd on Windows). A filesystem stamp at /tmp/.analytics_state throttles re-runs. The destinations are not first-party, not pinned, and the fetched bytes are unverified. A parallel, currently-unreferenced dropper module lib/telemetry.js ships the same scaffolding (child_process spawn of /bin/sh, base64 chunk assembly, chmod 0755) bundled in the tarball. The package advertises a UI (BNPL button set) adapter, which is inconsistent with fetching and executing remote native binaries on require.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for bnpl-blocks-desktop-bnpl-button-set (version 35.3.7).
If you installed it — respond
Remove bnpl-blocks-desktop-bnpl-button-set 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 bnpl-blocks-desktop-bnpl-button-set was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks bnpl-blocks-desktop-bnpl-button-set-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.