Which versions of sm-checkout are malicious?

The following npm versions of sm-checkout are flagged malicious: 99.0.0, 99.0.1. Treat any of these as compromised.

How do I remediate sm-checkout if I installed it?

sm-checkout 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 sm-checkout — how do I know if it already compromised me?

If sm-checkout 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 sm-checkout part of a known attack campaign?

Yes — sm-checkout is associated with the IN-MAL-2026-018610, IN-MAL-2026-018606 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 sm-checkout 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 sm-checkout (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging sm-checkout across your stack and pipelines.

Malicious package

sm-checkoutnpm

sm-checkout is a confirmed malicious npm package (MAL-2026-14397) that opens a backdoor for remote access (malicious versions 99.0.0, 99.0.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in sm-checkout (npm)

MAL-2026-14397

Immediate action

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

npm uninstall sm-checkout

What this malware does

[email protected] declares preinstall and postinstall lifecycle scripts in package.json that invoke curl against a hardcoded bare-IP URL over plain HTTP (http://16.192.173.5/sm-checkout/pre and http://16.192.173.5/sm-checkout/post) on npm install. The inflated 99.0.0 version is calibrated to win semver resolution against a private package of the same name, and the lifecycle callbacks confirm successful execution on any host that mistakenly resolves the public name, leaking the installer's source IP and install timing to the operator of 16.192.173.5. A source comment self-labels the package as a dependency-confusion test; the labelling does not change that the artifact runs an unauthenticated outbound beacon on every install in build systems and developer machines that pull it.

The OpenSSF Package Analysis project identified 'sm-checkout' @ 99.0.1 (npm) as malicious.

It is considered malicious because:

The package executes one or more commands associated with malicious behavior.

Malicious versions

2 flagged

99.0.099.0.1

Indicators of compromise (SHA-256)

0bc8dabb0ecf46dc57dd07dacdf28c9cddf629ffb8e9b0cea75e71cd999feaf0

b682bb5f16534282e26636060e35b1ad04fbbc6832539a79bd2c1c2a3b04e169

7e0e304166bd31c7677998bce3b0fa29ce87fcf40861c714a8f69417fc1083d1

Detection & response playbook

Backdoor / remote access

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for sm-checkout (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging sm-checkout across your stack and pipelines.
If you installed it — respond
sm-checkout 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 sm-checkout 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 sm-checkout 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. sm-checkout on npm has been identified as a malicious package (versions 99.0.0, 99.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-018610IN-MAL-2026-018606

References

Credits

Amazon Inspector · finder
OpenSSF: Package Analysis · finder

Detect & block this

O3 blocks sm-checkout-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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