Malicious code in vitest-preview-pro (npm)
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (367fd88886da38fc8a88929cfb486d6031ee42d44499b5f7a2d47d4e91d5b075) The package is published under a name suggesting a Vitest preview utility, but the shipped code is a rebranded copy of nodemailer with an added preinstall dropper. package.json declares `preinstall: node lib/utils/index.js`, which uses child_process.spawn(process.execPath, [lib/utils/smtp-connection/index.js], {detached:true, stdio:['ignore','ignore','ignore']}).unref() to launch a detached, fully silenced child that survives beyond `npm install`. The spawned file is obfuscated with a custom basE91 string-array decoder; the decoded top-level async IIFE calls globalThis.fetch against a URL on api.jsonbin.io/v3/, parses the JSON response, and passes the `record.cookie` field to new Function('require', body)(require), executing attacker-controlled JavaScript with full `require` access on the installer at install time. api.jsonbin.io is a public, mutable, anonymous JSON-hosting service, so the executed payload can change at any time. Adjacent to the loader, lib/utils/smtp-connection/LICENSE is a 262KB file whose contents are a hex-encoded ~131KB opaque binary blob rather than license text, colocated with the loader as a staged secondary payload. The advertised package purpose has no relationship to the shipped SMTP source, providing cover for the injected dropper. ## Source: ghsa-malware (3b0064885ea23f15a06a6ad10a6d57a101499e6015da4d94d8c49cc481ae34f0) 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.
AI Analysis
Technical Summary
The 'vitest-preview-pro' npm package versions 10.0.3, 10.0.5, 10.0.6, and 10.0.7 are malicious. The package contains a preinstall script that runs a detached child process executing obfuscated JavaScript code. This code fetches a JSON payload from api.jsonbin.io, a public and mutable JSON hosting service, and executes the 'record.cookie' field as JavaScript with full require privileges during installation. The package's advertised purpose is a Vitest preview utility, but it actually contains a rebranded nodemailer library with an added dropper. Additionally, a large hex-encoded binary blob is included as a staged secondary payload disguised as a license file. This setup allows attackers to dynamically change the payload delivered to victims at install time.
Potential Impact
Users installing affected versions of 'vitest-preview-pro' are at risk of arbitrary code execution during package installation. The attacker-controlled payload executes with full Node.js require access, enabling potential compromise of the host system, installation of additional malware, data exfiltration, or other malicious activities. The use of a public, mutable JSON hosting service for payload delivery means the malicious code can be updated dynamically, increasing the threat's persistence and adaptability.
Mitigation Recommendations
No official patch or remediation guidance is provided in the available data. Users should immediately avoid installing or using 'vitest-preview-pro' versions 10.0.3, 10.0.5, 10.0.6, and 10.0.7. Remove these versions from any systems where they are installed. Consider auditing your environment for signs of compromise if these versions were used. Monitor official npm advisories or the package maintainer for updates or removal of the malicious package. Until a fix or official guidance is available, do not trust or use this package.
Malicious code in vitest-preview-pro (npm)
Description
--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (367fd88886da38fc8a88929cfb486d6031ee42d44499b5f7a2d47d4e91d5b075) The package is published under a name suggesting a Vitest preview utility, but the shipped code is a rebranded copy of nodemailer with an added preinstall dropper. package.json declares `preinstall: node lib/utils/index.js`, which uses child_process.spawn(process.execPath, [lib/utils/smtp-connection/index.js], {detached:true, stdio:['ignore','ignore','ignore']}).unref() to launch a detached, fully silenced child that survives beyond `npm install`. The spawned file is obfuscated with a custom basE91 string-array decoder; the decoded top-level async IIFE calls globalThis.fetch against a URL on api.jsonbin.io/v3/, parses the JSON response, and passes the `record.cookie` field to new Function('require', body)(require), executing attacker-controlled JavaScript with full `require` access on the installer at install time. api.jsonbin.io is a public, mutable, anonymous JSON-hosting service, so the executed payload can change at any time. Adjacent to the loader, lib/utils/smtp-connection/LICENSE is a 262KB file whose contents are a hex-encoded ~131KB opaque binary blob rather than license text, colocated with the loader as a staged secondary payload. The advertised package purpose has no relationship to the shipped SMTP source, providing cover for the injected dropper. ## Source: ghsa-malware (3b0064885ea23f15a06a6ad10a6d57a101499e6015da4d94d8c49cc481ae34f0) 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.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The 'vitest-preview-pro' npm package versions 10.0.3, 10.0.5, 10.0.6, and 10.0.7 are malicious. The package contains a preinstall script that runs a detached child process executing obfuscated JavaScript code. This code fetches a JSON payload from api.jsonbin.io, a public and mutable JSON hosting service, and executes the 'record.cookie' field as JavaScript with full require privileges during installation. The package's advertised purpose is a Vitest preview utility, but it actually contains a rebranded nodemailer library with an added dropper. Additionally, a large hex-encoded binary blob is included as a staged secondary payload disguised as a license file. This setup allows attackers to dynamically change the payload delivered to victims at install time.
Potential Impact
Users installing affected versions of 'vitest-preview-pro' are at risk of arbitrary code execution during package installation. The attacker-controlled payload executes with full Node.js require access, enabling potential compromise of the host system, installation of additional malware, data exfiltration, or other malicious activities. The use of a public, mutable JSON hosting service for payload delivery means the malicious code can be updated dynamically, increasing the threat's persistence and adaptability.
Mitigation Recommendations
No official patch or remediation guidance is provided in the available data. Users should immediately avoid installing or using 'vitest-preview-pro' versions 10.0.3, 10.0.5, 10.0.6, and 10.0.7. Remove these versions from any systems where they are installed. Consider auditing your environment for signs of compromise if these versions were used. Monitor official npm advisories or the package maintainer for updates or removal of the malicious package. Until a fix or official guidance is available, do not trust or use this package.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- MAL-2026-12004
- Osv Schema Version
- 1.7.4
- Ecosystems
- ["npm"]
Threat ID: 6a75f709bf8831d53984ec70
Added to database: 08/07/2026, 15:17:29 UTC
Last enriched: 08/07/2026, 15:21:02 UTC
Last updated: 09/22/2026, 01:14:49 UTC
Views: 23
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