MAL-2026-12178 Malicious code in fb-cards-form-no-resident-information (npm)

On require() of the package, index.js loads adapter.js which reconstructs Cloudflare Workers hostnames from split string fragments (e.g. 'oob-worker' + '.cf101-a' + 'df.workers.dev') and downloads a platform-specific binary via https.get. A DNS TXT resolver fallback against subdomains of dl.well1.site retrieves a base64-chunked payload across numbered subdomains as an out-of-band channel. The fetched bytes are written to /tmp or %TEMP% under disguised names (.cache<rnd>, dotnet_diag_<rnd>.exe), chmod 0755, and spawned detached via spawn('/bin/sh', ['-c', fp+' &'], {detached:true}) or spawn('cmd',…). No hash or signature verification is performed; the destinations are unrelated to the package's stated purpose and are not publisher-owned infrastructure. An opt-out environment variable check is present as a cover story.

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.