Which versions of checkout-use-toasts are malicious?

The following npm versions of checkout-use-toasts are flagged malicious: 35.3.6. Treat any of these as compromised.

How do I remediate checkout-use-toasts if I installed it?

Remove checkout-use-toasts 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.

I already installed checkout-use-toasts — how do I know if it already compromised me?

If checkout-use-toasts 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.

Is checkout-use-toasts part of a known attack campaign?

Yes — checkout-use-toasts is associated with the IN-MAL-2026-015176 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-use-toasts across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for checkout-use-toasts (version 35.3.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging checkout-use-toasts across your stack and pipelines.

Malicious package

checkout-use-toastsnpm

checkout-use-toasts is a confirmed malicious npm package (MAL-2026-12603) that executes malicious code on install (malicious version 35.3.6). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in checkout-use-toasts (npm)

MAL-2026-12603

Immediate action

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

npm uninstall checkout-use-toasts

What this malware does

On require() of checkout-use-toasts, index.js loads bridge.js which fetches an OS/architecture-specific native binary from runtime-assembled Cloudflare workers.dev hosts (oob-worker.cf100/cf101/cf102-*.workers.dev) with a DNS-TXT fallback that resolves TXT records at subdomains of dl.wel1.ru and concatenates base64-decoded chunks as the payload. The bytes are written to /var/tmp/.cache<hex> (or %TEMP%\dotnet_diag_<hex>.exe on Windows) under disguised names, chmod 0755, and spawned detached via /bin/sh -c or cmd /c start /b. Destination hostnames are split into fragments and joined at runtime (['oob-worker.cf102-baf.wor','ke','rs','.d','ev'].join(''); ['sdk.d','l.','we','l1.','ru'].join('')) to evade static string matching. There is no signature or version pinning on the fetched payload. The package name and stated purpose (toast notifications for checkout flows) do not match downloading and executing a native binary, and the DNS-TXT covert channel is designed to bypass HTTP egress controls. Installing or importing this package results in attacker-controlled code execution on the installer's machine.

Malicious versions

1 flagged

35.3.6

Indicators of compromise (SHA-256)

bed98d203bbb9cb1a915db70566cfe33eb063a59e97c1e2f7607164b5a9c312e

Detection & response playbook

Malicious package

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for checkout-use-toasts (version 35.3.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging checkout-use-toasts across your stack and pipelines.
If you installed it — respond
Remove checkout-use-toasts 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-use-toasts 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-use-toasts 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

No. checkout-use-toasts on npm has been identified as a malicious package (version 35.3.6 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015176

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks checkout-use-toasts-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.

Malware detection Runtime egress monitoring

Explore

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