Which versions of checkout-pay-widget-logic are malicious?

The following npm versions of checkout-pay-widget-logic are flagged malicious: 35.3.2. Treat any of these as compromised.

How do I remediate checkout-pay-widget-logic if I installed it?

checkout-pay-widget-logic establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.

I already installed checkout-pay-widget-logic — how do I know if it already compromised me?

If checkout-pay-widget-logic 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.

Is checkout-pay-widget-logic part of a known attack campaign?

Yes — checkout-pay-widget-logic is associated with the IN-MAL-2026-015190 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find checkout-pay-widget-logic across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for checkout-pay-widget-logic (version 35.3.2).

Malicious package

checkout-pay-widget-logicnpm

Advisory published Aug 5, 2026Updated Aug 5, 2026

checkout-pay-widget-logic is a confirmed malicious npm package (MAL-2026-12585) that opens a backdoor for remote access (malicious version 35.3.2). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in checkout-pay-widget-logic (npm)

MAL-2026-12585

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall checkout-pay-widget-logic

What this malware does

On require('checkout-pay-widget-logic'), index.js loads./vendor.js which downloads a platform-specific binary over HTTPS from hardcoded Cloudflare Workers hosts (oob-worker.cf*.workers.dev), with a DNS TXT fallback under *.dl.wel1.ru that reassembles base64 chunks from TXT records. C2 hostnames are assembled at runtime by joining split string fragments to evade static detection. The fetched binary is written to /tmp or %TEMP% under disguised names (.cache<hex> on Unix, dotnet_diag_<hex>.exe on Windows, mimicking a Microsoft diagnostic tool), chmodded 0755, and spawned detached via /bin/sh -c or cmd.exe with stdio ignored. A lock file named.analytics_state and 'telemetry'-labeled functions provide a cover story; the package's stated purpose is a 'log formatter'. Environment-variable opt-outs exist but the dropper runs by default.

Malicious versions

1 flagged

35.3.2

Indicators of compromise (SHA-256)

3e25e8d60e2b9eb81d9e5de2e374fbf25b352e666d163d445461be9ac837669f

Detection & response playbook

Backdoor / remote access

Find it
Search your lockfiles and build artifacts for checkout-pay-widget-logic (version 35.3.2).
If you installed it — respond
checkout-pay-widget-logic establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If checkout-pay-widget-logic 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

No. checkout-pay-widget-logic on npm has been identified as a malicious package (version 35.3.2 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015190

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks checkout-pay-widget-logic-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.

Malware detection Runtime egress monitoring

Explore

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