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 ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.

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?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for sheratan_haha (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging sheratan_haha across your stack and pipelines.

Malicious package

sheratan_hahanpm

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
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for sheratan_haha (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging sheratan_haha across your stack and pipelines.
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 ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks sheratan_haha before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.

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

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