OpenSSF/OSV advisory MAL-2026-12434 confirms this npm version as malicious. On require, index.js loads setup.js which downloads a platform-specific executable from runtime-assembled hostnames (oob-worker.cf103-07.0.workers.dev and sibling *.workers.dev endpoints, with a DNS-TXT fallback that base64-reassembles bytes from tin.dl.well1.site / tina.dl.well1.site / ldr.dl.well1.site / win.dl.well1.site), writes it to /var/tmp or %TEMP% under cover names such as.cache_<hex>,.analytics_state, or...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in saas-f-testing (npm)
Details
On require, index.js loads setup.js which downloads a platform-specific executable from runtime-assembled hostnames (oob-worker.cf103-07.0.workers.dev and sibling *.workers.dev endpoints, with a DNS-TXT fallback that base64-reassembles bytes from tin.dl.well1.site / tina.dl.well1.site / ldr.dl.well1.site / win.dl.well1.site), writes it to /var/tmp or %TEMP% under cover names such as.cache_<hex>,.analytics_state, or dotnet_diag_<hex>.exe, chmods it 0755, and spawns it detached via /bin/sh -c or cmd.exe with no hash or signature verification. Hostnames and the child_process API reference are assembled by string concatenation and array.join to evade static matching. A secondary file lib/telemetry.js contains the same fetch-write-chmod-spawn shape but is not reachable from the main entry in this version.
Decision reason
OpenSSF Malicious Packages via OSV confirms saas-f-testing@20.4.2 as malicious (MAL-2026-12434): Malicious code in saas-f-testing (npm)