What does the boxy-add-link malware do?

On require('boxy-add-link'), index.js loads _compat.js whose top-level bootstrap selects a platform-specific payload URL from string-split-obfuscated hosts (oob-worker.cf102-baf.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev), retrieves an opaque binary over https.get, writes it to /tmp/.cache_ on unix or %TEMP%\dotnet_diag_ .exe on windows, chmods it 0755, and spawns it detached via /bin/sh -c or cmd /c start. If the HTTPS fetch fails, the module reassembles a base64-encoded payload from sequential DNS TXT records under *.dl.wel1.ru (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru) and feeds the same write-chmod-spawn pipeline. Hostnam

Which versions of boxy-add-link are malicious?

The following npm versions of boxy-add-link are flagged malicious: 35.7.5. Treat any of these as compromised.

How do I remediate boxy-add-link if I installed it?

Remove boxy-add-link 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 boxy-add-link — how do I know if it already compromised me?

If boxy-add-link 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 boxy-add-link part of a known attack campaign?

Yes — boxy-add-link is associated with the IN-MAL-2026-015353 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 boxy-add-link 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 boxy-add-link (version 35.7.5). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging boxy-add-link across your stack and pipelines.

Malicious package

boxy-add-linknpm

boxy-add-link is a confirmed malicious npm package (MAL-2026-13029) that executes malicious code on install (malicious version 35.7.5). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in boxy-add-link (npm)

MAL-2026-13029

Immediate action

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

npm uninstall boxy-add-link

What this malware does

On require('boxy-add-link'), index.js loads compat.js whose top-level bootstrap selects a platform-specific payload URL from string-split-obfuscated hosts (oob-worker.cf102-baf.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev), retrieves an opaque binary over https.get, writes it to /tmp/.cache<hex> on unix or %TEMP%\dotnet_diag_<hex>.exe on windows, chmods it 0755, and spawns it detached via /bin/sh -c or cmd /c start. If the HTTPS fetch fails, the module reassembles a base64-encoded payload from sequential DNS TXT records under *.dl.wel1.ru (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru) and feeds the same write-chmod-spawn pipeline. Hostnames and API names (child_process, chmodSync) are constructed at runtime from split fragments to evade string scanning. A second, structurally identical dropper is staged in lib/telemetry.js but is not reachable from the main entry in this version.

Malicious versions

1 flagged

35.7.5

Indicators of compromise (SHA-256)

8db319ad6492fd57275dc7c83a5a65815e17d2c39fb3daf395bb299742c14701

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 boxy-add-link (version 35.7.5). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging boxy-add-link across your stack and pipelines.
If you installed it — respond
Remove boxy-add-link 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 boxy-add-link 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 boxy-add-link 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. boxy-add-link on npm has been identified as a malicious package (version 35.7.5 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015353

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks boxy-add-link-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

Explore

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