Which versions of claims-get-error-string are malicious?

The following npm versions of claims-get-error-string are flagged malicious: 35.5.9. Treat any of these as compromised.

How do I remediate claims-get-error-string if I installed it?

Remove claims-get-error-string 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-get-error-string — how do I know if it already compromised me?

If claims-get-error-string 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-get-error-string part of a known attack campaign?

Yes — claims-get-error-string is associated with the IN-MAL-2026-015153 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-get-error-string 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-get-error-string (version 35.5.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging claims-get-error-string across your stack and pipelines.

Malicious package

claims-get-error-stringnpm

claims-get-error-string is a confirmed malicious npm package (MAL-2026-12620) that executes malicious code on install (malicious version 35.5.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in claims-get-error-string (npm)

MAL-2026-12620

Immediate action

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

npm uninstall claims-get-error-string

What this malware does

On require(), index.js loads ext.js which downloads a platform-specific binary from a set of hardcoded Cloudflare Workers hosts (oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev, oob-worker.cf100-416.workers.dev) assembled by string-splitting to evade static matching. The downloaded bytes are written to /var/tmp or %TEMP% under innocuous names (.cache<rnd> on POSIX, dotnet_diag_<rnd>.exe on Windows), chmod 0755 is applied, and the binary is spawned detached via /bin/sh -c '<path> &' or cmd. A DNS-TXT covert channel under wel1.ru (sdk.dl.wel1.ru, ext.dl.wel1.ru, pkg.dl.wel1.ru, net.dl.wel1.ru) reads a chunk count from c.<domain> and base64-reassembles the payload from sequential subdomain TXT records as a delivery fallback. A second module lib/telemetry.js (81KB) is bundled in the tarball with parallel dropper logic (base64 chunk assembly, chmod 0755, cp.spawn('/bin/sh', ['-c', filePath+' &'])) though not reachable from main in this version. No hash pinning, no signature verification, opaque payload, cover-story naming as analytics/telemetry.

Malicious versions

1 flagged

35.5.9

Indicators of compromise (SHA-256)

8107a092447bc749767928c38a816191c2af0ea06cb12d6dbeddb9f09b46c698

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-get-error-string (version 35.5.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging claims-get-error-string across your stack and pipelines.
If you installed it — respond
Remove claims-get-error-string 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-get-error-string 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-get-error-string 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-get-error-string on npm has been identified as a malicious package (version 35.5.9 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015153

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks claims-get-error-string-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

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