Which versions of fastly-vcl-language-client are malicious?

The following npm versions of fastly-vcl-language-client are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate fastly-vcl-language-client if I installed it?

fastly-vcl-language-client 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 fastly-vcl-language-client — how do I know if it already compromised me?

If fastly-vcl-language-client 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 fastly-vcl-language-client part of a known attack campaign?

Yes — fastly-vcl-language-client is associated with the IN-MAL-2026-017959 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 fastly-vcl-language-client 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 fastly-vcl-language-client (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 fastly-vcl-language-client across your stack and pipelines.

Malicious package

fastly-vcl-language-clientnpm

fastly-vcl-language-client is a confirmed malicious npm package (MAL-2026-14060) 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 fastly-vcl-language-client (npm)

MAL-2026-14060

Immediate action

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

npm uninstall fastly-vcl-language-client

What this malware does

The package declares scripts.preinstall = 'node vishu.js', which runs unconditionally on npm install. vishu.js fetches the installer's public IP via api.ipify.org, reads os.hostname(), and collects CI runner environment variables (CI, GITHUB_ACTIONS, GITHUB_WORKFLOW, GITHUB_RUN_ID, GITHUB_RUN_NUMBER, GITHUB_RUN_ATTEMPT) from process.env, then POSTs/GETs the collected data to a hardcoded https://webhook.site/3c201be4-c16d-4e0c-bf9c-ccc50faa8574 endpoint. It additionally performs a DNS lookup of ping-<hostname>.<oast-collaborator-domain> to exfiltrate the hostname via DNS out-of-band. The package ships no real functionality — its metadata describes it as a 'dependency test utility package' and its name resembles an internal Fastly tool, consistent with a dependency-confusion / recon probe targeting build systems that resolve internal package names against public npm.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

2f77be5ce1488e7867223b63fd5c90060e98d6a44325ff2f71bed2b61653d649

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 fastly-vcl-language-client (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 fastly-vcl-language-client across your stack and pipelines.
If you installed it — respond
fastly-vcl-language-client 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 fastly-vcl-language-client 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 fastly-vcl-language-client 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. fastly-vcl-language-client 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

IN-MAL-2026-017959

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks fastly-vcl-language-client-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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