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 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 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?

Search your lockfiles and build artifacts for wct-st (version 1.0.0).

Malicious package

wct-stnpm

Advisory published Aug 13, 2026Updated Aug 13, 2026

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
Search your lockfiles and build artifacts for wct-st (version 1.0.0).
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 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. 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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