MAL-2026-17766 Malicious code in @s4yhiitestpoc/scan-https-d (npm)

Dependency-confusion proof-of-concept package. A postinstall script runs automatically on installation and sends host and user identifiers (hostname, username, home directory, network interface addresses, platform details and npm configuration) to collector.oob.s4yhii.com, with a secondary DNS lookup under oob.s4yhii.com. The script states it is bug-bounty research and does not read secrets or file contents. Any machine that installed this package disclosed the listed host information to a third party.

On npm install, postinstall.js collects installer host identity — os.hostname(), os.userInfo().username, home directory, cwd, non-internal network interface addresses, DNS servers, and platform/arch/release — and POSTs it as JSON over HTTPS to the hardcoded endpoint https://collector.oob.s4yhii.com/_npm-poc/beacon, with a secondary DNS lookup against *.oob.s4yhii.com as an out-of-band execution signal. The package's scope (@s4yhiitestpoc/*) and metadata self-describe this as a dependency-confusion proof-of-concept targeting internal namespaces that resolve to the public registry; the self-labeling does not change the fact that installer host identifiers leave the installer's machine on install to a hardcoded third-party domain the installer did not opt into.

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.