Which versions of sheratan_haha are malicious?

The following npm versions of sheratan_haha are flagged malicious: 1.0.0, 1.0.1. Treat any of these as compromised.

How do I remediate sheratan_haha if I installed it?

sheratan_haha 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 sheratan_haha — how do I know if it already compromised me?

If sheratan_haha 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 sheratan_haha part of a known attack campaign?

Yes — sheratan_haha is associated with the IN-MAL-2026-006360, IN-MAL-2026-006361, IN-MAL-2026-006359 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 sheratan_haha across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for sheratan_haha (2 malicious versions).

Malicious package

sheratan_hahanpm

Advisory published Jun 13, 2026Updated Jun 13, 2026

sheratan_haha is a confirmed malicious npm package (MAL-2026-5739) that steals credentials and exfiltrates sensitive data (malicious versions 1.0.0, 1.0.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in sheratan_haha (npm)

MAL-2026-5739

Immediate action

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

npm uninstall sheratan_haha

What this malware does

On npm install, the package's declared postinstall hook (node postinstall.js) runs whoami on the installer's machine and POSTs the output to a hardcoded webhook.site endpoint (https://webhook.site/0ea9eb45-3ede-4cf0-9ea9-2b8d700272e7) via https.request. The package advertises itself as 'A simple date formatting utility' but ships no library code consistent with that purpose — the only behavior on install is host fingerprinting and exfiltration to an attacker-controlled URL. Metadata is placeholder-shaped (empty author, generic description, name sheratan_haha), consistent with a dependency-confusion / recon PoC. Installing this package leaks the installer's OS username to an external endpoint controlled by the publisher.

Malicious versions

2 flagged

1.0.01.0.1

Indicators of compromise (SHA-256)

5417b03a148421c99e85e5179f9911aadfe5ad30144fa4c3bf0eb1cbd8fc2160

6b473b40e0c041d34e85161ed8c91e0e00d006a0822698a0d3994876cb685ddd

8425e7844278696c1b266519af201afa5e89ef4cf8fa0ad7da38a297fcdbbe2f

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for sheratan_haha (2 malicious versions).
If you installed it — respond
sheratan_haha 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 sheratan_haha 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. sheratan_haha on npm has been identified as a malicious package (versions 1.0.0, 1.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-006360IN-MAL-2026-006361IN-MAL-2026-006359

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks sheratan_haha-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