cardsmobile-data-utilsnpm
Advisory published Updated
cardsmobile-data-utils is a confirmed malicious npm package (MAL-2026-12531) that executes malicious code on install (malicious version 35.6.2). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in cardsmobile-data-utils (npm)
What this malware does
On require() of cardsmobile-data-utils, index.js loads./vendor.js, which downloads a platform-specific native executable over HTTPS from hardcoded Cloudflare Workers hosts (oob-worker.cf103-070.workers.dev, oob-worker.cf102-baf.workers.dev, oob-worker.cf101-adf.workers.dev) with a DNS-TXT chunked fallback to *.dl.wel1.ru, writes it under /var/tmp or %TEMP% with a randomized name, chmods it 0755 on Unix, and spawns it detached via /bin/sh -c or cmd. No hash or signature verification is performed and the destinations are unrelated to the package's advertised 'helper methods' purpose. Hostnames and sensitive API names are assembled from split string fragments (['oob-wor','ker.cf101-a','df','.workers.','dev'].join(''), 'child'+'process', fs['chmod'+'Sync']) to evade static inspection. A second copy of the download-write-chmod-spawn chain is shipped in lib/telemetry.js (~81 KB) disguised as an APM/telemetry SDK, with base64-decoded payload buffering and the same detached shell spawn, providing a redundant staged payload in the tarball.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for cardsmobile-data-utils (version 35.6.2).
If you installed it — respond
Remove cardsmobile-data-utils from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If cardsmobile-data-utils was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks cardsmobile-data-utils-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.