Which versions of vitest-agent are malicious?

The following npm versions of vitest-agent are flagged malicious: 1.0.5, 1.0.6. Treat any of these as compromised.

How do I remediate vitest-agent if I installed it?

Remove vitest-agent from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.

I already installed vitest-agent — how do I know if it already compromised me?

If vitest-agent 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 vitest-agent part of a known attack campaign?

Yes — vitest-agent is associated with the IN-MAL-2026-007874, IN-MAL-2026-007873 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 vitest-agent 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 vitest-agent (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging vitest-agent across your stack and pipelines.

Malicious package

vitest-agentnpm

Malicious code in vitest-agent (npm) Remove it immediately and rotate any exposed credentials.

MAL-2026-6710

Immediate action

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

npm uninstall vitest-agent

What this malware does

The package's postinstall script (node lib/utils/index.js) spawns a detached, stdio-suppressed Node child process that runs lib/utils/smtp-connection/index.js. That file fetches JavaScript from https://jsonkeeper.com/b/WDH3V via axios and executes the response with new Function("require", r.data.cookie)(require), running unpinned, mutable, non-publisher code on the installer's machine at npm install time. The package is named vitest-agent but its main and shipped source are a verbatim copy of nodemailer (author field Andris Reinman, description is an unrelated React copyright string), a name/identity mismatch consistent with a lure targeting vitest ecosystem users. Concealment signals reinforce the dropper: a ~256 KB LICENSE file sits adjacent to a 185-byte dropper index.js under lib/utils/smtp-connection/, and path names mirror legitimate nodemailer layout as cover. Because the harmful code path fires automatically from the postinstall lifecycle hook, installers are compromised without any explicit user action beyond installing the package.

Malicious versions

2 flagged

1.0.51.0.6

Indicators of compromise (SHA-256)

6e0165cbb3d6ed37a96889c4b016463706346e1c09413635c31ea1ceedde8774

c3f7ebf642b562d3c33e78df9352951379038121536b34dc0a358e3dc5a6343e

Detection & response playbook

Malicious package

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for vitest-agent (2 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging vitest-agent across your stack and pipelines.
If you installed it — respond
Remove vitest-agent from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If vitest-agent 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 vitest-agent 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. vitest-agent on npm has been identified as a malicious package (versions 1.0.5, 1.0.6 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-007874IN-MAL-2026-007873

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks vitest-agent-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring