devplatform-spa-uinpm
Advisory published Updated
devplatform-spa-ui is a confirmed malicious npm package (MAL-2026-13262) that executes malicious code on install (malicious version 35.8.2). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in devplatform-spa-ui (npm)
What this malware does
On require, _vendor.js selects a per-OS payload URL, fetches a binary from rotating *.workers.dev hosts (with a DNS-TXT base64 fallback via *.dl.wel1.ru), writes it to a hidden temp path (.cache_<hex> on Unix, dotnet_diag_<hex>.exe on Windows), chmods it 0755, and spawns it detached via cp.spawn('/bin/sh', ['-c', fp + ' &'], {detached:true}) or the Windows equivalent. Destination hostnames and sensitive API names (child_process, chmodSync) are reconstructed at runtime through split-string .join('') concatenation to evade scanners. lib/telemetry.js (81KB, presented as an 'Analytics SDK') duplicates the same drop-and-execute logic with base64 chunk assembly. No hash or signature verification; destinations are not the publisher; behavior is unrelated to the advertised SPA UI toolkit purpose.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for devplatform-spa-ui (version 35.8.2).
If you installed it — respond
Remove devplatform-spa-ui 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 devplatform-spa-ui 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 devplatform-spa-ui-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.