Which versions of claims-patch-url are malicious?

The following npm versions of claims-patch-url are flagged malicious: 35.3.9. Treat any of these as compromised.

How do I remediate claims-patch-url if I installed it?

claims-patch-url 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 claims-patch-url — how do I know if it already compromised me?

If claims-patch-url 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-patch-url part of a known attack campaign?

Yes — claims-patch-url is associated with the IN-MAL-2026-015140 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-patch-url 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-patch-url (version 35.3.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging claims-patch-url across your stack and pipelines.

Malicious package

claims-patch-urlnpm

claims-patch-url is a confirmed malicious npm package (MAL-2026-12631) that opens a backdoor for remote access (malicious version 35.3.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in claims-patch-url (npm)

MAL-2026-12631

Immediate action

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

npm uninstall claims-patch-url

What this malware does

[email protected] presents an empty ClaimsPatchUrl shell class in index.js and unconditionally requires./compat.js on load. On require(), compat.js selects a platform-specific endpoint, downloads an opaque binary from one of four split-concatenated Cloudflare Worker hosts (oob-worker.cf100-.workers.dev through oob-worker.cf103-.workers.dev) with a DNS-TXT resolveTxt covert-channel fallback under *.dl.wel1.ru, writes the payload to /var/tmp or TEMP under cover-story filenames (dotnet_diag<hex>.exe,.cache<hex>,.analytics_state), chmods it 0755, and spawns it detached via /bin/sh -c or cmd. C2 hostnames are reassembled at runtime via array-join to evade static analysis, and DISABLE_TELEMETRY / DO_NOT_TRACK env checks are used as benign-looking gates. The package's declared API is an empty class; the only functional path is the dropper. Package identity (generic 'Claims patch url runtime support module' description, no dependencies, unused 81KB lib/telemetry.js sibling) is consistent with a typosquat/decoy.

Malicious versions

1 flagged

35.3.9

Indicators of compromise (SHA-256)

c07292652ca72654d945a2833f8cf8915ea79f1ce665a0445938ff2605394c08

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 claims-patch-url (version 35.3.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging claims-patch-url across your stack and pipelines.
If you installed it — respond
claims-patch-url 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 claims-patch-url 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-patch-url 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-patch-url on npm has been identified as a malicious package (version 35.3.9 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-015140

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks claims-patch-url-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

Explore

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