Which versions of wct-st are malicious?

The following npm versions of wct-st are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate wct-st if I installed it?

wct-st 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 wct-st — how do I know if it already compromised me?

If wct-st 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 wct-st part of a known attack campaign?

Yes — wct-st is associated with the IN-MAL-2026-017710 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 wct-st 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 wct-st (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging wct-st across your stack and pipelines.

Malicious package

wct-stnpm

wct-st is a confirmed malicious npm package (MAL-2026-13990) that opens a backdoor for remote access (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in wct-st (npm)

MAL-2026-13990

Immediate action

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

npm uninstall wct-st

What this malware does

On npm install, the package's postinstall lifecycle script collects installer host identifiers (hostname, platform, architecture, Node.js version, package name, npm lifecycle event) and POSTs them as JSON to the hardcoded remote endpoint https://bhvte4h4.instances.poc.jchunt.top/wct-st. The beacon fires automatically with no consent, configuration, or opt-out. The package name resembles the deprecated web-component-tester, consistent with a typosquat / dependency-confusion beacon shape.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

3065a54d66ae4872334224443453c85f98c9ab8ae9d87df215bb51a5ba5e7595

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 wct-st (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging wct-st across your stack and pipelines.
If you installed it — respond
wct-st 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 wct-st 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 wct-st 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. wct-st on npm has been identified as a malicious package (version 1.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-017710

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks wct-st-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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