Which versions of @posthog/plugin-unduplicates are malicious?

The following npm versions of @posthog/plugin-unduplicates are flagged malicious: 0.0.8. Treat any of these as compromised.

How do I remediate @posthog/plugin-unduplicates if I installed it?

@posthog/plugin-unduplicates is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.

I already installed @posthog/plugin-unduplicates — how do I know if it already compromised me?

If @posthog/plugin-unduplicates 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.

How do I find @posthog/plugin-unduplicates across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for @posthog/plugin-unduplicates (version 0.0.8).

Part of a larger attack: @posthog published 56 malicious packages. See the full campaign →

Malicious package

@posthog/plugin-unduplicatesnpm

Advisory published Nov 24, 2025Updated Nov 26, 2025

@posthog/plugin-unduplicates is a confirmed malicious npm package (MAL-2025-190889) that steals credentials and exfiltrates sensitive data (malicious version 0.0.8). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in @posthog/plugin-unduplicates (npm)

MAL-2025-190889

Immediate action

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

npm uninstall @posthog/plugin-unduplicates

What this malware does

The package @posthog/plugin-unduplicates was found to contain malicious code.

This package was compromised by the Sha1-Hulud: The Second Coming NPM worm. The malicious payload steals tokens and credentials and publishes them to GitHub. The worm will propogate itself to NPM packages the user owns and establish persistence is a GitHub action. The package may also destroy the user's home directory.

Malicious versions

1 flagged

0.0.8

Indicators of compromise (SHA-256)

5c908d2f59bb746353f63ff6561e3e99d8055d86ee72332228bfd40f24b8dad0

a9f0c1b760ff4d5ee2d63b7f5acc8086319f310deead542b3c2b677554374947

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for @posthog/plugin-unduplicates (version 0.0.8).
If you installed it — respond
@posthog/plugin-unduplicates is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If @posthog/plugin-unduplicates 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. @posthog/plugin-unduplicates on npm has been identified as a malicious package (version 0.0.8 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks @posthog/plugin-unduplicates-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

Explore

All malware advisories How O3 detects malware Vulnerability database