What does the boxy-mops malware do?

On require(), boxy-mops loads _compat.js, which assembles attacker-controlled hostnames from split string fragments (resolving to oob-worker.cf1XX-XXX.workers.dev and the *.dl.wel1.ru family: sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru), performs an HTTPS GET for a platform-specific binary, writes the bytes under disguised names (.cache_ on Unix, dotnet_diag_ .exe on Windows) into /tmp or %TEMP%, chmods the file 0755, and detach-spawns it via /bin/sh -c or cmd.exe /c start with unref(). A DNS TXT chunked fallback channel is present for exfiltration/instruction retrieval when HTTPS is blocked. Runtime string reconstruction is used to hide destination hosts from sta

Which versions of boxy-mops are malicious?

The following npm versions of boxy-mops are flagged malicious: 35.2.9. Treat any of these as compromised.

How do I remediate boxy-mops if I installed it?

boxy-mops is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.

I already installed boxy-mops — how do I know if it already compromised me?

If boxy-mops 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-mops part of a known attack campaign?

Yes — boxy-mops is associated with the IN-MAL-2026-015312 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-mops 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-mops (version 35.2.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging boxy-mops across your stack and pipelines.

Malicious package

boxy-mopsnpm

boxy-mops is a confirmed malicious npm package (MAL-2026-13073) that steals credentials and exfiltrates sensitive data (malicious version 35.2.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in boxy-mops (npm)

MAL-2026-13073

Immediate action

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

npm uninstall boxy-mops

What this malware does

On require(), boxy-mops loads compat.js, which assembles attacker-controlled hostnames from split string fragments (resolving to oob-worker.cf1XX-XXX.workers.dev and the *.dl.wel1.ru family: sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru), performs an HTTPS GET for a platform-specific binary, writes the bytes under disguised names (.cache<hex> on Unix, dotnet_diag_<hex>.exe on Windows) into /tmp or %TEMP%, chmods the file 0755, and detach-spawns it via /bin/sh -c or cmd.exe /c start with unref(). A DNS TXT chunked fallback channel is present for exfiltration/instruction retrieval when HTTPS is blocked. Runtime string reconstruction is used to hide destination hosts from static inspection; a DISABLE_TELEMETRY / DO_NOT_TRACK environment guard suppresses execution on analyst machines; a /tmp/.analytics_state cache stamp gates repeat runs. The advertised 'telemetry/analytics' framing does not match the observed behavior — the package fetches and executes opaque non-publisher binaries on the installer's host at import time.

Malicious versions

1 flagged

35.2.9

Indicators of compromise (SHA-256)

d377c600e4c23a91ca7b5c4465804849e0427d7f14392877ad961244142fe477

Detection & response playbook

Credential / info stealer

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for boxy-mops (version 35.2.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging boxy-mops across your stack and pipelines.
If you installed it — respond
boxy-mops is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If boxy-mops 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-mops 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-mops on npm has been identified as a malicious package (version 35.2.9 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015312

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks boxy-mops-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

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