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 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 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?

Search your lockfiles and build artifacts for boxy-add-link (version 35.7.5).

Malicious package

boxy-add-linknpm

Advisory published Aug 5, 2026Updated Aug 5, 2026

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
Search your lockfiles and build artifacts for boxy-add-link (version 35.7.5).
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 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. 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

All malware advisories How O3 detects malware Vulnerability database