Which versions of checkout-public-tokens are malicious?

The following npm versions of checkout-public-tokens are flagged malicious: 35.4.9. Treat any of these as compromised.

How do I remediate checkout-public-tokens if I installed it?

Remove checkout-public-tokens 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-public-tokens — how do I know if it already compromised me?

If checkout-public-tokens 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-public-tokens part of a known attack campaign?

Yes — checkout-public-tokens is associated with the IN-MAL-2026-015188 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-public-tokens across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for checkout-public-tokens (version 35.4.9).

Malicious package

checkout-public-tokensnpm

Advisory published Aug 5, 2026Updated Aug 5, 2026

checkout-public-tokens is a confirmed malicious npm package (MAL-2026-12589) that executes malicious code on install (malicious version 35.4.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in checkout-public-tokens (npm)

MAL-2026-12589

Immediate action

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

npm uninstall checkout-public-tokens

What this malware does

On require() of checkout-public-tokens, index.js loads platform.js which downloads an opaque binary payload from hardcoded string-split-obfuscated hosts (oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev), with a DNS-TXT base64 fallback resolver via sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The payload is written to /tmp or %TEMP% under a disguised name (.cache<hex> or dotnet_diag_<hex>.exe), chmodded to 0755, and spawned detached via /bin/sh -c or cmd.exe /c start /b. Destination hostnames are constructed at runtime by joining split literals, and in-file comments frame the download-and-execute chain as telemetry, analytics, and cache validation. The package advertises itself as a token utility; the hosts and behavior are unrelated to any documented purpose and there is no hash or signature verification of the fetched bytes.

Malicious versions

1 flagged

35.4.9

Indicators of compromise (SHA-256)

c1ca81222c080449cad71d071579738ea810e280c6e8ed3b53647efdde902536

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for checkout-public-tokens (version 35.4.9).
If you installed it — respond
Remove checkout-public-tokens 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-public-tokens 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-public-tokens on npm has been identified as a malicious package (version 35.4.9 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015188

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks checkout-public-tokens-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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