boxy-use-what-changednpm
boxy-use-what-changed is a confirmed malicious npm package (MAL-2026-13095) that executes malicious code on install (malicious version 35.4.4). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in boxy-use-what-changed (npm)
What this malware does
On require() of boxy-use-what-changed, index.js loads ext.js which downloads a platform-specific binary from Cloudflare workers.dev subdomains (oob-worker.cf100-416.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf99-9b3.workers.dev), with a DNS TXT-record fallback under dl.wel1.ru (sdk.dl.wel1.ru, net.dl.wel1.ru). Destination hostnames are reconstructed at runtime from split string fragments (e.g. ["oob-worker.cf","100-416.worke","rs.dev"].join("")) to evade static string matching. The fetched payload is written to a disguised path in /tmp or %TEMP% (.cache<hex> or dotnet_diag_<hex>.exe), chmod 0o755, and executed detached via cp.spawn("/bin/sh", ["-c", path+" &"], {detached:true}) or the Windows cmd equivalent. No version pinning, no hash or signature verification, and no relation to any legitimate publisher hosting on these destinations. A second file, lib/telemetry.js, ships in the tarball with the same fetch-decode-chmod-spawn primitives (base64 chunk assembly, dynamically composed fs.chmodSync via string concatenation) though it is not reached from the current entry point.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for boxy-use-what-changed (version 35.4.4). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging boxy-use-what-changed across your stack and pipelines.
If you installed it — respond
Remove boxy-use-what-changed 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-use-what-changed 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-use-what-changed 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
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks boxy-use-what-changed-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.