Which versions of checkout-accounts-holder are malicious?

The following npm versions of checkout-accounts-holder are flagged malicious: 35.2.3. Treat any of these as compromised.

How do I remediate checkout-accounts-holder if I installed it?

Remove checkout-accounts-holder 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-accounts-holder — how do I know if it already compromised me?

If checkout-accounts-holder 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-accounts-holder part of a known attack campaign?

Yes — checkout-accounts-holder is associated with the IN-MAL-2026-015228 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-accounts-holder 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-accounts-holder (version 35.2.3). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging checkout-accounts-holder across your stack and pipelines.

Malicious package

checkout-accounts-holdernpm

checkout-accounts-holder is a confirmed malicious npm package (MAL-2026-12541) that executes malicious code on install (malicious version 35.2.3). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in checkout-accounts-holder (npm)

MAL-2026-12541

Immediate action

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

npm uninstall checkout-accounts-holder

What this malware does

On require('checkout-accounts-holder'), index.js loads _platform.js which immediately downloads a platform-specific binary over HTTPS from hostnames assembled at runtime via .join("") over split string fragments (resolving to oob-worker.cf100-416.workers.dev with a DNS TXT fallback under sdk.dl.wel1.ru), writes the opaque payload to /tmp or %TEMP% under cover names such as .cache_<rand> and dotnet_diag_<rand>.exe, chmods it 0o755, and spawns it detached via /bin/sh -c "<path> &" or cmd.exe /c start. The module presents itself as analytics_state/telemetry. A second dropper of the same shape ships in lib/telemetry.js (base64-chunked payload, fs["chmod"+"Sync"], require("child_"+"process"), spawn("/bin/sh", ["-c", filePath + " &"])), currently unreferenced but present in the published tarball. Destination hostnames are string-split to evade plain-text scanners, and the run-write-chmod-spawn chain executes attacker-controlled bytes with the installer's privileges.

Malicious versions

1 flagged

35.2.3

Indicators of compromise (SHA-256)

cd25bb3af3a1501bd4ea34cf95d79c43340a06ff801f144564819e3bf8bf078a

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-accounts-holder (version 35.2.3). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging checkout-accounts-holder across your stack and pipelines.
If you installed it — respond
Remove checkout-accounts-holder 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-accounts-holder 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-accounts-holder 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-accounts-holder on npm has been identified as a malicious package (version 35.2.3 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015228

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks checkout-accounts-holder-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

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