Which versions of postcss-hotfix are malicious?

The following npm versions of postcss-hotfix are flagged malicious: 2.0.0, 77.7.7, 99.9.9. Treat any of these as compromised.

How do I remediate postcss-hotfix if I installed it?

Remove postcss-hotfix 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 postcss-hotfix — how do I know if it already compromised me?

If postcss-hotfix 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 postcss-hotfix part of a known attack campaign?

Yes — postcss-hotfix is associated with the RLMA-2026-01503 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 postcss-hotfix across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for postcss-hotfix (3 malicious versions).

Malicious package

postcss-hotfixnpm

Advisory published Mar 18, 2026Updated Mar 23, 2026

postcss-hotfix is a confirmed malicious npm package (MAL-2026-1822) that executes malicious code on install (malicious versions 2.0.0, 77.7.7, 99.9.9). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in postcss-hotfix (npm)

MAL-2026-1822

Immediate action

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

npm uninstall postcss-hotfix

What this malware does

The package postcss-hotfix was found to contain malicious code.

Malicious versions

3 flagged

2.0.077.7.799.9.9

Indicators of compromise (SHA-256)

1dd4632b3e21468017f17dd7ab366cf5564307e5ee57f86eda942c389462db76

b5b4d8ad8f9c133d2d8680b4d666d442b455bbd1579dea5cd5582a883fc4f0b5

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for postcss-hotfix (3 malicious versions).
If you installed it — respond
Remove postcss-hotfix 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 postcss-hotfix 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. postcss-hotfix on npm has been identified as a malicious package (versions 2.0.0, 77.7.7, 99.9.9 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-01503

Credits

Amazon Inspector · finder
ReversingLabs · finder

Detect & block this

O3 blocks postcss-hotfix-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

Explore

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