Which versions of npm-hex-utils are malicious?

The following npm versions of npm-hex-utils are flagged malicious: 1.1.1. Treat any of these as compromised.

How do I remediate npm-hex-utils if I installed it?

npm-hex-utils 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 npm-hex-utils — how do I know if it already compromised me?

If npm-hex-utils 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 npm-hex-utils part of a known attack campaign?

Yes — npm-hex-utils is associated with the IN-MAL-2026-017644 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 npm-hex-utils across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for npm-hex-utils (version 1.1.1).

Malicious package

npm-hex-utilsnpm

Advisory published Aug 13, 2026Updated Aug 13, 2026

npm-hex-utils is a confirmed malicious npm package (MAL-2026-13956) that opens a backdoor for remote access (malicious version 1.1.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in npm-hex-utils (npm)

MAL-2026-13956

Immediate action

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

npm uninstall npm-hex-utils

What this malware does

The package's postinstall runs runtime.js, which POSTs os.hostname(), os.userInfo().username, os.platform()+os.arch(), Node version, and OS release to https://steel-mere-4155.ricardorichp.workers.dev/report, then fetches an encrypted blob from https://steel-mere-4155.ricardorichp.workers.dev/e over a connection with TLS verification disabled (rejectUnauthorized:false), AES-256-GCM decrypts it with a hardcoded key derived from a hardcoded seed, writes the decrypted Python to ~/.cache/hex-encode-utils/modules/runtime.py, and spawns python detached with stdio ignored to execute it. Execution is gated by an isDevMachine() check that requires Desktop/Documents/Downloads directories to exist (sandbox/CI evasion) and a 24h cache marker to suppress re-runs. Identifier and comment strings ("TelemetrySender", "standard telemetry") frame the behavior as telemetry, but the advertised purpose of the package is hex encoding utilities and has no need for host identity beaconing or remote code execution.

Malicious versions

1 flagged

1.1.1

Indicators of compromise (SHA-256)

6a0f1f9004b6a502c144d4d475e89a3956905aebf51fb2696d4ba05c21613727

Detection & response playbook

Backdoor / remote access

Find it
Search your lockfiles and build artifacts for npm-hex-utils (version 1.1.1).
If you installed it — respond
npm-hex-utils 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 npm-hex-utils 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. npm-hex-utils on npm has been identified as a malicious package (version 1.1.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-017644

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks npm-hex-utils-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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