Malicious code in serpacksven1 (npm)

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (20d4a6a2715973b427bb0aa2b7a493ca711b7f16b5f47f90062edf790e0186a6) The tarball ships no JavaScript — the declared `main: index.js` is absent — and contains only 10 byte-identical copies of a PowerShell dropper under misleading extensions (`1.png`, `client.doc`, `client.doc.1`, `json.txt`, extensionless `client`, all sha256 e9dff494...). The script hides the console window via Win32 APIs, concatenates ~150 base64 chunks, XOR-decodes them with single-byte key 89, reflectively resolves `[System.Reflection.Assembly].Load` through char-code-obfuscated type strings, and invokes the decoded in-memory.NET assembly. The package has no lifecycle scripts and no importable surface, so `npm install` alone does not execute the payload; the harm fires when a second-stage tool or downstream workflow sources any of the disguised files (e.g. `powershell -File client.doc`), delivering full-host code execution of an attacker-controlled.NET assembly on Windows. The multi-extension disguise, byte-identical duplication, and absence of any legitimate package content show this is a payload-staging artifact published to npm rather than a software package. ## Source: ghsa-malware (d0730e12f59904bd205a2a840fce1dbab41414538d235ea91ddb3a23cc2a0b8f) 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.

Source published

5 Oct 2026 17:31:00 UTC

Source modified

6 Oct 2026 04:30:45 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.