Which versions of checkout-legal-logic are malicious?

The following npm versions of checkout-legal-logic are flagged malicious: 35.3.7. Treat any of these as compromised.

How do I remediate checkout-legal-logic if I installed it?

Remove checkout-legal-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.

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

If checkout-legal-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.

Is checkout-legal-logic part of a known attack campaign?

Yes — checkout-legal-logic is associated with the IN-MAL-2026-015212 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-legal-logic 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-legal-logic (version 35.3.7). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging checkout-legal-logic across your stack and pipelines.

Malicious package

checkout-legal-logicnpm

checkout-legal-logic is a confirmed malicious npm package (MAL-2026-12569) 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 checkout-legal-logic (npm)

MAL-2026-12569

Immediate action

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

npm uninstall checkout-legal-logic

What this malware does

On require of the package's main entry (index.js -> support.js), a bootstrap routine downloads a platform-specific executable from one of four hardcoded Cloudflare Workers subdomains (oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev), with a DNS TXT record fallback under sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. The fetched bytes are written to /tmp or %TEMP% under disguised names (.cache<rand>, dotnet_diag_<rand>.exe), chmod 0755, and spawned detached via /bin/sh -c or cmd.exe /c start /b. All hostnames and paths are reconstructed at runtime via array.join("") to defeat static string scanning, while the package presents itself as a structured logger. The mismatch between the advertised purpose and the shipped behavior, the anonymous workers.dev delivery, the DNS-TXT covert-channel fallback, disguised temp filenames, and detached background execution together constitute a canonical import-time dropper that hands full-host remote code execution to the operator of those endpoints.

Malicious versions

1 flagged

35.3.7

Indicators of compromise (SHA-256)

cb3515ded3bbec7c93c9544b3ad8dee138c5a41252dfc5dca9ff8f8854c088c5

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-legal-logic (version 35.3.7). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging checkout-legal-logic across your stack and pipelines.
If you installed it — respond
Remove checkout-legal-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-legal-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-legal-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

No. checkout-legal-logic on npm has been identified as a malicious package (version 35.3.7 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015212

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks checkout-legal-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.

Malware detection Runtime egress monitoring

Explore

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