What does the devplatform-spa-testing malware do?

On `require('devplatform-spa-testing')`, index.js loads _platform.js which selects a platform-specific endpoint, retrieves a payload over HTTPS from string-concatenated `oob-worker.cf*.workers.dev` hostnames (with a DNS-TXT-chunked base64 fallback via `sdk.dl.wel1.ru`), writes it to /tmp or %TEMP% under a disguised name (`.cache_ ` on POSIX or `dotnet_diag_ .exe` on Windows), chmods 0755, and spawns it detached via `/bin/sh -c` or `cmd`. The C2 hostnames are assembled by joining fragments (e.g. `['oob-w','orker.cf102-','baf.worke','rs.d','ev'].join('')`) to defeat plain string scanning, and the dropper filenames plus cover-story comments about telemetry opt-out mask the behavior. T

Which versions of devplatform-spa-testing are malicious?

The following npm versions of devplatform-spa-testing are flagged malicious: 35.8.6. Treat any of these as compromised.

How do I remediate devplatform-spa-testing if I installed it?

devplatform-spa-testing establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.

I already installed devplatform-spa-testing — how do I know if it already compromised me?

If devplatform-spa-testing 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 devplatform-spa-testing part of a known attack campaign?

Yes — devplatform-spa-testing is associated with the IN-MAL-2026-014992, GHSA-w476-3rpv-vw8r 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-spa-testing 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 devplatform-spa-testing (version 35.8.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging devplatform-spa-testing across your stack and pipelines.

Malicious package

devplatform-spa-testingnpm

devplatform-spa-testing is a confirmed malicious npm package (MAL-2026-12784) that opens a backdoor for remote access (malicious version 35.8.6). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in devplatform-spa-testing (npm)

MAL-2026-12784

Immediate action

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

npm uninstall devplatform-spa-testing

What this malware does

On require('devplatform-spa-testing'), index.js loads _platform.js which selects a platform-specific endpoint, retrieves a payload over HTTPS from string-concatenated oob-worker.cf*.workers.dev hostnames (with a DNS-TXT-chunked base64 fallback via sdk.dl.wel1.ru), writes it to /tmp or %TEMP% under a disguised name (.cache_<rand> on POSIX or dotnet_diag_<rand>.exe on Windows), chmods 0755, and spawns it detached via /bin/sh -c or cmd. The C2 hostnames are assembled by joining fragments (e.g. ['oob-w','orker.cf102-','baf.worke','rs.d','ev'].join('')) to defeat plain string scanning, and the dropper filenames plus cover-story comments about telemetry opt-out mask the behavior. The fetched bytes are attacker-controlled and executed on the installer's machine at import time.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

Malicious versions

1 flagged

35.8.6

Indicators of compromise (SHA-256)

d43b8f8982db0f563db0d728dbc9ecdd9907e29dd45f2d9bf42e0c8416fc80fa

94d0aab60461539f1d9e4e5025f28d7fa38653699dd1bc05009d46bae9a90a4c

Detection & response playbook

Backdoor / remote access

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for devplatform-spa-testing (version 35.8.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging devplatform-spa-testing across your stack and pipelines.
If you installed it — respond
devplatform-spa-testing establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If devplatform-spa-testing 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 devplatform-spa-testing 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. devplatform-spa-testing on npm has been identified as a malicious package (version 35.8.6 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-014992GHSA-w476-3rpv-vw8r

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks devplatform-spa-testing-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.

Malware detection Runtime egress monitoring

Explore

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