registry / typesens / 1.0.0

typesens@1.0.0

OSV Malicious Advisory

imported 3d ago · by OpenSSF/OSV

OpenSSF/OSV advisory MAL-2026-17565 confirms this npm version as malicious. package.json declares postinstall `wscript.exe 4444.vbs`, which runs automatically on `npm install`. The shipped 4444.vbs (~765 KB) contains a multi-layer decryption chain (AES S-box, ChaCha20-IETF, SHA-256 constants XOR-masked with 0x5A5A5A5A) over ~665 base64 chunks, decodes a payload to %TEMP% as a.dat file, drops a PowerShell loader, and invokes powershell.exe to perform process hollowing on Windows...

Advisory

MAL-2026-17565

Source

OpenSSF Malicious Packages via OSV

Summary

Malicious code in typesens (npm)

Details

package.json declares postinstall `wscript.exe 4444.vbs`, which runs automatically on `npm install`. The shipped 4444.vbs (~765 KB) contains a multi-layer decryption chain (AES S-box, ChaCha20-IETF, SHA-256 constants XOR-masked with 0x5A5A5A5A) over ~665 base64 chunks, decodes a payload to %TEMP% as a.dat file, drops a PowerShell loader, and invokes powershell.exe to perform process hollowing on Windows. Function names in the VBS are randomized (PlatformProbeLVI, DeviceCatalogUBYQ, EndpointRegistryRFX) and the `CreateObject` target is XOR-decoded at runtime; a cover-story header labels the file as a 'Verdant Signals Corp Device Telemetry Aggregator'. The advertised library surface — src/index.js is a trivial zod-based email-domain check with no network I/O, and the README claims 'No installation scripts' and describes a 'booking-eligibility' utility — is a decoy contradicting the package.json `files` entry that ships 4444.vbs and the postinstall hook that runs it. The typosquat-shaped name (typesens) reinforces the lure framing.

Decision reason

OpenSSF Malicious Packages via OSV confirms typesens@1.0.0 as malicious (MAL-2026-17565): Malicious code in typesens (npm)

References

OSV advisory PACKAGE

Source & flagged code

0 flagged

No flagged code excerpts are attached to this scan.

Source & flagged code

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Findings

1 High

HighOsv Malicious Advisory

Affected versions and remediation

This report applies to typesens@1.0.0.

See version security history for other recorded verdicts.

Avoid installing typesens@1.0.0. Remove it from direct dependencies and check your lockfile for transitive copies.
Choose an independently verified alternative or release. This report does not establish that other versions are safe.
If this version ran, investigate the affected machine and build environment. Rotate credentials it could access and rebuild from a trusted environment.

Evidence last updated: 2026-10-05 04:15:05.707Z (UTC).

Source advisory published: 2026-10-05 03:37:54.000Z (UTC).

This report uses published external intelligence. The advisory does not provide a separate source-code analysis for each listed version.