Which versions of claims-enums are malicious?

The following npm versions of claims-enums are flagged malicious: 35.7.6. Treat any of these as compromised.

How do I remediate claims-enums if I installed it?

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

If claims-enums 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 claims-enums part of a known attack campaign?

Yes — claims-enums is associated with the IN-MAL-2026-015152 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-enums 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 claims-enums (version 35.7.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging claims-enums across your stack and pipelines.

Malicious package

claims-enumsnpm

claims-enums is a confirmed malicious npm package (MAL-2026-12614) that executes malicious code on install (malicious version 35.7.6). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in claims-enums (npm)

MAL-2026-12614

Immediate action

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

npm uninstall claims-enums

What this malware does

On require('claims-enums'), index.js loads polyfill.js which selects a platform-specific asset path and fetches an opaque binary over HTTPS from hardcoded Cloudflare Workers subdomains (oob-worker.cf101-adf.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev), with DNS-TXT chunked fallbacks resolved from sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, and net.dl.wel1.ru. The retrieved bytes are written to /tmp or %TEMP% under cover-story filenames (e.g. dotnet_diag<hex>.exe,.cache_<hex>), chmod'd 0755, and detach-spawned via /bin/sh or cmd.exe. Hostnames, the child_process import, and fs.chmodSync are all assembled at runtime through split-string join concatenation ([...].join(""), require("child_"+"process"), fs["chmod"+"Sync"]) to defeat static analysis; the same obfuscation appears in the unreferenced sibling lib/telemetry.js. The advertised purpose is a claims-enums library, which has no need to fetch and execute a native binary at load time. A DISABLE_TELEMETRY environment check is present as cover framing.

Malicious versions

1 flagged

35.7.6

Indicators of compromise (SHA-256)

b20ec13ad19307ce64881191637d062bff5e53301ad75001de1b0974d5d0161e

Detection & response playbook

Malicious package

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for claims-enums (version 35.7.6). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging claims-enums across your stack and pipelines.
If you installed it — respond
Remove claims-enums 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-enums 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 claims-enums 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. claims-enums on npm has been identified as a malicious package (version 35.7.6 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015152

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks claims-enums-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