Which versions of clients-structure are malicious?

The following npm versions of clients-structure are flagged malicious: 35.9.8. Treat any of these as compromised.

How do I remediate clients-structure if I installed it?

Remove clients-structure 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 clients-structure — how do I know if it already compromised me?

If clients-structure 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 clients-structure part of a known attack campaign?

Yes — clients-structure is associated with the IN-MAL-2026-015125 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 clients-structure 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 clients-structure (version 35.9.8). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging clients-structure across your stack and pipelines.

Malicious package

clients-structurenpm

clients-structure is a confirmed malicious npm package (MAL-2026-12649) that executes malicious code on install (malicious version 35.9.8). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in clients-structure (npm)

MAL-2026-12649

Immediate action

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

npm uninstall clients-structure

What this malware does

On require() of clients-structure, index.js loads _ext.js which selects a platform-specific endpoint, fetches a binary from a rotating list of anonymous Cloudflare Workers subdomains (oob-worker.cf101-adf.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev), with a DNS-TXT fallback channel over sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru that reconstructs a base64 payload chunked across numbered TXT records. The fetched bytes are written to a temp path, chmod 0755, and spawned detached via /bin/sh -c or cmd.exe. Destination hostnames are assembled at runtime from split string fragments joined via Array.join, and a /tmp/.analytics_state TTL marker plus an opt-out env-var facade serve as cover story. No hash or signature verification is performed, and the destinations bear no relation to any declared publisher.

Malicious versions

1 flagged

35.9.8

Indicators of compromise (SHA-256)

5dc3674a31787baaf2d3d554336f507ecce91da7b4d527a170c50cd720024d48

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 clients-structure (version 35.9.8). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging clients-structure across your stack and pipelines.
If you installed it — respond
Remove clients-structure 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 clients-structure 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 clients-structure 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. clients-structure on npm has been identified as a malicious package (version 35.9.8 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015125

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks clients-structure-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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