delivery-ci-storybook@35.5.8
Malicious code in delivery-ci-storybook (npm)
Analysis
On require(), the package fingerprints the host platform/arch and downloads a second-stage binary over HTTPS from Cloudflare Workers endpoints oob-worker[.]cf100-416[.]workers[.]dev, oob-worker[.]cf99-9b3[.]workers[.]dev, and oob-worker[.]cf101-adf[.]workers[.]dev (paths /pkg/package, /pkg/package-arm64, /pkg/loader_mac, /pkg/package.exe). If the HTTPS fetch fails it retrieves the payload via DNS TXT queries to c[.]sdk[.]dl[.]wel1[.]ru (discovery domains sdk[.]dl[.]wel1[.]ru, ext[.]dl[.]wel1[.]ru, pkg[.]dl[.]wel1[.]ru, net[.]dl[.]wel1[.]ru). The downloaded payload is written to /tmp/.cache_<hex> (or %TEMP%\dotnet_diag_<hex>.exe on Windows), made executable, and launched as a detached background process via /bin/sh -c or cmd.exe /c start /b. The package's declared purpose (a storybook adapter) does not involve downloading or executing remote binaries.
- analyzed by
- Leitwacht
- first seen
- Aug 5, 2026, 01:30 PM
- analyzed
- Aug 5, 2026, 02:57 PM
Related advisories
- devplatform-spa-plugin-sentry@35.1.1
- dolyame-boxy-desktop-bnpl-button-set@35.2.4
- devplatform-spa-plugin-module-loader@35.8.5
- devplatform-spa-di@35.5.8
- dolyame-ui-footer@35.5.8
- devplatform-spa-plugin-thermostat@35.9.9
- devplatform-vite-plugin-gle@35.3.9
- devplatform-s3-uploader@35.4.4
Independently detected by the Leitwacht supply-chain probe. IOCs are defanged. Published CC0. Think this is a mistake? See the dispute policy.