Which versions of fast-csv-helper are malicious?

The following npm versions of fast-csv-helper are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate fast-csv-helper if I installed it?

fast-csv-helper 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 fast-csv-helper — how do I know if it already compromised me?

If fast-csv-helper 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 fast-csv-helper part of a known attack campaign?

Yes — fast-csv-helper is associated with the GHSA-c65v-4v4c-jcpr, IN-MAL-2026-011247 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 fast-csv-helper 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 fast-csv-helper (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging fast-csv-helper across your stack and pipelines.

Malicious package

fast-csv-helpernpm

fast-csv-helper is a confirmed malicious npm package (MAL-2026-11462) that steals credentials and exfiltrates sensitive data (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in fast-csv-helper (npm)

MAL-2026-11462

Immediate action

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

npm uninstall fast-csv-helper

What this malware does

Package name typosquats the popular fast-csv CSV library but has no CSV functionality. lib/report.js collects the installer's git/GitHub email by invoking gh api user/emails, running git config user.email, reading ~/.gitconfig and npm config, and inspecting GIT_*/EMAIL environment variables, together with os.userInfo() username and os.hostname(). The collected identity payload is POSTed via https.request to the hardcoded third-party webhook https://hooks.zapier.com/hooks/catch/28124699/42vdpup/. The postinstall path is gated by a consent-flag file, and the CLI path issues a one-shot prompt before sending; both ultimately deliver installer identity to an author-controlled endpoint. The package.json description self-labels the code as a 'harmless security research payload,' which does not alter the behavior: it is a live typosquat on the public npm registry that enumerates developers who fat-finger fast-csv.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

ca3596032239f2a982b11e2846e8af25975d77f3f7c211a32f68e5a451ead883

6808d5469c720a0a26411e9def23ca8bf9be60193c696057e2e6378c3ef51640

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 fast-csv-helper (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging fast-csv-helper across your stack and pipelines.
If you installed it — respond
fast-csv-helper 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 fast-csv-helper 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 fast-csv-helper 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. fast-csv-helper on npm has been identified as a malicious package (version 1.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

GHSA-c65v-4v4c-jcprIN-MAL-2026-011247

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks fast-csv-helper-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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