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 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.

Malicious versions

1 flagged

35.8.6

Indicators of compromise (SHA-256)

d43b8f8982db0f563db0d728dbc9ecdd9907e29dd45f2d9bf42e0c8416fc80fa

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-2026-014992

References

npmjs.com

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

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