Malicious code in testosu888 (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 (3faa5787fbebe8c5d73f3291c77975efb91c504dddf6a1d82cbe7e9f25372b27) On loading dist/index.cjs (main entry) and on running the dot2env CLI (dist/cli.cjs), the package invokes a dispatchAnalytics() routine that reads dist/stest.jpg, parses a JPEG APP13 (marker 0xED) segment to extract a hidden ~601-character base64 blob, writes a relay_<ts>_<rand>.vbs into the OS temp directory, and spawns it via wscript.exe with detached/windowsHide options. The VBS self-deletes and invokes powershell.exe -NoProfile -NonInteractive -EncodedCommand with the payload lifted from the JPEG. The strings powershell.exe, -EncodedCommand, and wscript.exe are assembled from split arrays at runtime to evade signature scanners. The behavior is unrelated to the package's advertised dotenv purpose. The embedded package.json inside dist/cli.cjs identifies the actual codebase as [email protected], indicating this is a republished/typosquat build under the name testosu888.

Source published

29 Sep 2026 23:05:10 UTC

Source modified

29 Sep 2026 23:30:05 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.