Which versions of boxy-expander-contract are malicious?

The following npm versions of boxy-expander-contract are flagged malicious: 35.5.3. Treat any of these as compromised.

How do I remediate boxy-expander-contract if I installed it?

Remove boxy-expander-contract 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-expander-contract — how do I know if it already compromised me?

If boxy-expander-contract 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-expander-contract part of a known attack campaign?

Yes — boxy-expander-contract is associated with the IN-MAL-2026-015344 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-expander-contract 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-expander-contract (version 35.5.3). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging boxy-expander-contract across your stack and pipelines.

Malicious package

boxy-expander-contractnpm

boxy-expander-contract is a confirmed malicious npm package (MAL-2026-13043) that executes malicious code on install (malicious version 35.5.3). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in boxy-expander-contract (npm)

MAL-2026-13043

Immediate action

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

npm uninstall boxy-expander-contract

What this malware does

On require() of this package, index.js loads./runtime.js which assembles Cloudflare Workers hostnames via string-split.join('') fragments (e.g. oob-worker.cf103-070.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf101-adf.workers.dev) with a DNS-TXT fallback under *.dl.wel1.ru (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru), downloads a platform-specific binary via https.get, writes it to /tmp or %TEMP% under a name masquerading as system tooling (dotnet_diag.exe,.cache_), chmods 755 on unix, and spawns it detached via spawn('/bin/sh', ['-c',...]) or spawn('cmd',...). No hash or signature verification is performed and destination hosts are string-fragmented to evade static analysis. The package's advertised API is an unrelated decoy stub.

Malicious versions

1 flagged

35.5.3

Indicators of compromise (SHA-256)

d1f5856de3b0385535e80e5ef85627ecb7a087132c82c5d5457b35b62b9eaf72

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-expander-contract (version 35.5.3). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging boxy-expander-contract across your stack and pipelines.
If you installed it — respond
Remove boxy-expander-contract 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-expander-contract 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-expander-contract 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-expander-contract on npm has been identified as a malicious package (version 35.5.3 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015344

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks boxy-expander-contract-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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