What does the devplatform-react-scripts malware do?

The package's index.js requires./_init on load. _init.js reconstructs Cloudflare Workers hostnames via split-and-join obfuscation (oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf102-baf.workers.dev) with a DNS-TXT base64 fallback under *.dl.wel1.ru, fetches a platform-specific binary over HTTPS, writes it to /var/tmp/.cache_ on Unix or %TEMP%\dotnet_diag_ .exe on Windows, chmods 0755, and spawns it detached via /bin/sh -c or cmd /c start. A.analytics_state marker file and env-var opt-out names (DISABLE_TELEMETRY, ANALYTICS_OPT_OUT, DO_NOT_TRACK) provide telemetry cover. The advertised 'react-scripts adapter' purpose does not match the dropped-and-exe

Which versions of devplatform-react-scripts are malicious?

The following npm versions of devplatform-react-scripts are flagged malicious: 35.2.9. Treat any of these as compromised.

How do I remediate devplatform-react-scripts if I installed it?

Remove devplatform-react-scripts 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 devplatform-react-scripts — how do I know if it already compromised me?

If devplatform-react-scripts 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 devplatform-react-scripts part of a known attack campaign?

Yes — devplatform-react-scripts is associated with the IN-MAL-2026-015040 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 devplatform-react-scripts across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for devplatform-react-scripts (version 35.2.9).

Malicious package

devplatform-react-scriptsnpm

Advisory published Aug 5, 2026Updated Aug 5, 2026

devplatform-react-scripts is a confirmed malicious npm package (MAL-2026-12741) that executes malicious code on install (malicious version 35.2.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in devplatform-react-scripts (npm)

MAL-2026-12741

Immediate action

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

npm uninstall devplatform-react-scripts

What this malware does

The package's index.js requires./init on load. init.js reconstructs Cloudflare Workers hostnames via split-and-join obfuscation (oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf102-baf.workers.dev) with a DNS-TXT base64 fallback under *.dl.wel1.ru, fetches a platform-specific binary over HTTPS, writes it to /var/tmp/.cache<hex> on Unix or %TEMP%\dotnet_diag<hex>.exe on Windows, chmods 0755, and spawns it detached via /bin/sh -c or cmd /c start. A.analytics_state marker file and env-var opt-out names (DISABLE_TELEMETRY, ANALYTICS_OPT_OUT, DO_NOT_TRACK) provide telemetry cover. The advertised 'react-scripts adapter' purpose does not match the dropped-and-executed opaque binary. Any consumer that installs and requires this package receives arbitrary attacker code execution on their machine.

Malicious versions

1 flagged

35.2.9

Indicators of compromise (SHA-256)

b482d551faa8ecb3cb337bd8bacfe5ec193f1bc2cad69b3998e935fbaf413efa

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for devplatform-react-scripts (version 35.2.9).
If you installed it — respond
Remove devplatform-react-scripts 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 devplatform-react-scripts 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. devplatform-react-scripts 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-2026-015040

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks devplatform-react-scripts-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

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