Which versions of capacity-capacity-core are malicious?

The following npm versions of capacity-capacity-core are flagged malicious: 35.3.7. Treat any of these as compromised.

How do I remediate capacity-capacity-core if I installed it?

Remove capacity-capacity-core 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 capacity-capacity-core — how do I know if it already compromised me?

If capacity-capacity-core 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 capacity-capacity-core part of a known attack campaign?

Yes — capacity-capacity-core is associated with the IN-MAL-2026-015253 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 capacity-capacity-core across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for capacity-capacity-core (version 35.3.7).

Malicious package

capacity-capacity-corenpm

Advisory published Aug 5, 2026Updated Aug 5, 2026

capacity-capacity-core is a confirmed malicious npm package (MAL-2026-12522) that executes malicious code on install (malicious version 35.3.7). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in capacity-capacity-core (npm)

MAL-2026-12522

Immediate action

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

npm uninstall capacity-capacity-core

What this malware does

On require of the package's main entry, adapter.js downloads a platform-specific binary from one of three string-split-obfuscated Cloudflare Workers hosts (oob-worker.cf101-adf.workers.dev, oob-worker.cf100-416.workers.dev, oob-worker.cf99-9b3.workers.dev), with a DNS TXT base64 fallback via sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. The fetched bytes are written to /tmp or %TEMP% under a disguised name (.cache<hex> on POSIX, dotnet_diag_<hex>.exe on Windows), chmod 0755, and detach-spawned via /bin/sh -c 'fp &' or cmd.exe /c start. A mtime marker at /tmp/.analytics_state throttles re-execution. Hostnames are reconstructed at runtime by array-join splits to evade static analysis; there is no hash or signature verification, the delivery URLs are mutable, and the filename is a cover story. Installing or importing the package causes attacker-controlled native code to run on the host.

Malicious versions

1 flagged

35.3.7

Indicators of compromise (SHA-256)

a6bca5365f5c34188532641c63143e3fd2306d2c7ffe64a78de98904c43d6b7c

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for capacity-capacity-core (version 35.3.7).
If you installed it — respond
Remove capacity-capacity-core 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 capacity-capacity-core 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. capacity-capacity-core on npm has been identified as a malicious package (version 35.3.7 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015253

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks capacity-capacity-core-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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