Which versions of hardhat-jsx are malicious?

The following npm versions of hardhat-jsx are flagged malicious: 2.0.1. Treat any of these as compromised.

How do I remediate hardhat-jsx if I installed it?

hardhat-jsx is a typosquat — you almost certainly intended a legitimately-named package. Remove hardhat-jsx, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.

I already installed hardhat-jsx — how do I know if it already compromised me?

If hardhat-jsx 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 hardhat-jsx part of a known attack campaign?

Yes — hardhat-jsx is associated with the IN-MAL-2026-020971 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 hardhat-jsx across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for hardhat-jsx (version 2.0.1).

Malicious package

hardhat-jsxnpm

Advisory published Oct 4, 2026Updated Oct 4, 2026

hardhat-jsx is a confirmed malicious npm package (MAL-2026-17507) that typosquats a legitimate package to trick installs (malicious version 2.0.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in hardhat-jsx (npm)

MAL-2026-17507

Immediate action

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

npm uninstall hardhat-jsx

What this malware does

The package is published as 'hardhat-jsx' but its metadata, documentation, and lib/ layout impersonate the pino logger (keywords 'fast','logger','stream','json'; shipped docs reference pinojs/pino). The main entry index.js unconditionally requires./lib/config, which is a 4,499,968-byte single-line obfuscator.io artifact — a hex-escaped string array of ~26,234 entries with string-array rotation and control-flow flattening (22,707 decoder-wrapper inlines, 44,499 string-inline changes). A legitimate pino 'config' module is ~1-2KB; a multi-megabyte obfuscated blob auto-loaded by the main entry is a loader/dropper. The surface index.js exports a no-op Express-style middleware whose comment claims it 'triggers a background process', providing a cover story adjacent to the obfuscated require. Loading the package via require/import executes the opaque payload in the installer's process. The name/content mismatch (hardhat-jsx vs. pino impersonation), the stub façade, and the heavily obfuscated auto-loaded module together form a trojan-package shape.

Malicious versions

1 flagged

2.0.1

Indicators of compromise (SHA-256)

62ac44be2745338b73861690e7f979216fdfc6c3797dfa2f450e9063aa4158d1

Detection & response playbook

Typosquat

Find it
Search your lockfiles and build artifacts for hardhat-jsx (version 2.0.1).
If you installed it — respond
hardhat-jsx is a typosquat — you almost certainly intended a legitimately-named package. Remove hardhat-jsx, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If hardhat-jsx 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. hardhat-jsx on npm has been identified as a malicious package (version 2.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-020971

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks hardhat-jsx-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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