Which versions of claims-microgen-templates are malicious?

The following npm versions of claims-microgen-templates are flagged malicious: 35.7.1. Treat any of these as compromised.

How do I remediate claims-microgen-templates if I installed it?

Remove claims-microgen-templates 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 claims-microgen-templates — how do I know if it already compromised me?

If claims-microgen-templates 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 claims-microgen-templates part of a known attack campaign?

Yes — claims-microgen-templates is associated with the IN-MAL-2026-015148 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 claims-microgen-templates across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for claims-microgen-templates (version 35.7.1).

Malicious package

claims-microgen-templatesnpm

Advisory published Aug 5, 2026Updated Aug 5, 2026

claims-microgen-templates is a confirmed malicious npm package (MAL-2026-12628) that executes malicious code on install (malicious version 35.7.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in claims-microgen-templates (npm)

MAL-2026-12628

Immediate action

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

npm uninstall claims-microgen-templates

What this malware does

On require of the package, index.js loads compat.js which fetches a platform-specific binary from string-concatenated Cloudflare Workers hosts (oob-worker.cf1-01-adf.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf103-070.workers.dev) with a DNS-TXT chunked fallback via sdk.dl.wel1.ru / ext.dl.wel1.ru / pkg.dl.wel1.ru / net.dl.wel1.ru. Destination hostnames are reassembled from split string arrays via.join() to evade static string scans, with decoy 'telemetry'/'analytics' comments. The fetched payload is written to a randomized dotfile under /var/tmp (or dotnet_diag*.exe under %TEMP% on Windows), chmodded 0755, and spawned detached via /bin/sh or cmd. Execution is gated by a /tmp/.analytics_state freshness marker. No hash/signature verification, no publisher-matching host, and no relation to the package's stated 'templates' purpose.

Malicious versions

1 flagged

35.7.1

Indicators of compromise (SHA-256)

9d4eefb6f5d91cfe86acf925e0d84b5cb34336f98cf73586e01d17418d02454f

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for claims-microgen-templates (version 35.7.1).
If you installed it — respond
Remove claims-microgen-templates 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 claims-microgen-templates 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. claims-microgen-templates on npm has been identified as a malicious package (version 35.7.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015148

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks claims-microgen-templates-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

All malware advisories How O3 detects malware Vulnerability database