Which versions of boxy-mmb-types are malicious?

The following npm versions of boxy-mmb-types are flagged malicious: 35.4.1. Treat any of these as compromised.

How do I remediate boxy-mmb-types if I installed it?

Remove boxy-mmb-types 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-mmb-types — how do I know if it already compromised me?

If boxy-mmb-types 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-mmb-types part of a known attack campaign?

Yes — boxy-mmb-types is associated with the IN-MAL-2026-015304 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-mmb-types across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for boxy-mmb-types (version 35.4.1).

Malicious package

boxy-mmb-typesnpm

Advisory published Aug 5, 2026Updated Aug 5, 2026

boxy-mmb-types is a confirmed malicious npm package (MAL-2026-13072) that executes malicious code on install (malicious version 35.4.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in boxy-mmb-types (npm)

MAL-2026-13072

Immediate action

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

npm uninstall boxy-mmb-types

What this malware does

index.js unconditionally require()s loader.js on module load. loader.js reconstructs hostnames by joining split string fragments (evading static grep) to build endpoints under oob-worker.cf*.workers.dev with a DNS-TXT fallback via *.dl.wel1.ru, fetches a platform-specific native binary via https.get, writes it to /var/tmp or %TEMP% under a disguised name (.cache<hex> on Unix, dotnet_diag<hex>.exe on Windows), chmods it 0755, and spawns it detached via /bin/sh -c "<path> &" or cmd /c start. A TTL marker gates re-execution. A bundled lib/telemetry.js (~81 KB) is not imported by any code path and functions as decoy content to make the package resemble a legitimate telemetry wrapper. The obfuscated hostname assembly, disguised filenames, no-op stderr writer, and DNS covert-channel fallback are attacker anti-analysis patterns paired with the drop-and-execute chain.

Malicious versions

1 flagged

35.4.1

Indicators of compromise (SHA-256)

f98f3a2dd8ca593bdd127f3fd631a10fe4a3c70f57890aa43e2da45b92d18d80

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for boxy-mmb-types (version 35.4.1).
If you installed it — respond
Remove boxy-mmb-types 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-mmb-types 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-mmb-types on npm has been identified as a malicious package (version 35.4.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015304

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks boxy-mmb-types-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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