checkout-mobile-pay-widgetnpm
Advisory published Updated
checkout-mobile-pay-widget is a confirmed malicious npm package (MAL-2026-12578) that steals credentials and exfiltrates sensitive data (malicious version 35.9.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in checkout-mobile-pay-widget (npm)
What this malware does
[email protected] is a dropper disguised as a mobile-payment/native-bridge SDK. On require() of the package, index.js unconditionally loads adapter.js, which at module load selects a platform-specific payload, downloads it from one of four Cloudflare Workers mirrors whose hostnames are reconstructed at runtime via array-join splits (e.g. ["oob-worker.cf101-adf.worke","rs.dev"].join("")), with a DNS-TXT chunked base64 covert channel over *.dl.wel1.ru as fallback. The downloaded bytes are written to /tmp/.cache<hex> on Unix or %TEMP%\dotnet_diag_<hex>.exe on Windows — cover-story names impersonating benign runtime artifacts — chmod'd 0755, and spawned detached via /bin/sh -c "<path> &" or cmd /c start /b. A stamp file /tmp/.analytics_state gates re-execution (EXPIRE_SEC=22056), stderr is stubbed to no-ops, and DISABLE_TELEMETRY-style env vars are honored to appear inert in sandboxes. No hash or signature verification is performed; the fetched bytes are attacker-controlled. The package advertises a native mobile-pay bridge but ships no such functionality — the only effect of installing/requiring it is the drop-and-exec chain.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Search your lockfiles and build artifacts for checkout-mobile-pay-widget (version 35.9.1).
If you installed it — respond
checkout-mobile-pay-widget 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 checkout-mobile-pay-widget 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 checkout-mobile-pay-widget-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.