Which versions of hex-type are malicious?

The following npm versions of hex-type are flagged malicious: 3.0.2. Treat any of these as compromised.

How do I remediate hex-type if I installed it?

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

If hex-type 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 hex-type part of a known attack campaign?

Yes — hex-type is associated with the IN-MAL-2026-005342, IN-MAL-2026-005341, GHSA-jc42-pxfc-29x3 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 hex-type across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for hex-type (version 3.0.2).

Malicious package

hex-typenpm

Advisory published Jun 11, 2026Updated Jun 11, 2026

hex-type is a confirmed malicious npm package (MAL-2026-5538) that opens a backdoor for remote access (malicious version 3.0.2). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in hex-type (npm)

MAL-2026-5538

Immediate action

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

npm uninstall hex-type

What this malware does

Package metadata (description "A universally-unique, lexicographically-sortable, identifier generator", homepage github.com/ulid/javascript, build script --name ulidx, reused ULID source) impersonates the legitimate ulid/ulidx libraries, but the package adds a malicious dropper not present in those projects. package.json declares "postinstall": "node dist/utils.js". On npm install, dist/utils.js re-spawns itself detached with --bg, copies dist/payload.js (~950KB) to a hidden directory named MicrosoftSystem64 under LOCALAPPDATA / Application Support / ~/.local/share (impersonating a Windows system component), and registers OS-level persistence: a Windows Scheduled Task plus Run-key launching wscript.exe of a generated VBS, a Linux systemd --user service with loginctl enable-linger, or a .config/autostart fallback, and a detached spawn on macOS. The dropped payload.js bundles the ws WebSocket client/server, pino logging, zod, and references https://huggingface.co/api and https://huggingface.co — the building blocks of a long-running remote-controlled agent, with zero relation to ULID generation. Both the postinstall (if (cpus.length <= 4...) return;) and the agent (MIN_CPU_COUNT = 5) abort on hosts with ≤4 CPUs to evade sandboxes and low-core CI runners. This is unambiguous installer-side RCE plus persistence plus C2.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

Malicious versions

1 flagged

3.0.2

Indicators of compromise (SHA-256)

1b9530df5da36f6e3de0761c79ef3687e4f0c5f1990d77a3f874df2c1b3fe278

f7d0271fe97ea66e9ff2ba3a0ea225364324f28138af32c337d6ed8b2b99e5ad

4a9a7e2427ae3c6ab1b50874653afe275962d527b94bf81ea5ce52ae9455d793

Detection & response playbook

Backdoor / remote access

Find it
Search your lockfiles and build artifacts for hex-type (version 3.0.2).
If you installed it — respond
hex-type 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 hex-type 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. hex-type on npm has been identified as a malicious package (version 3.0.2 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-005342IN-MAL-2026-005341GHSA-jc42-pxfc-29x3

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks hex-type-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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