platform-ui-islandnpm
platform-ui-island is a confirmed malicious npm package (MAL-2026-12042) that executes malicious code on install (malicious version 20.5.9). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in platform-ui-island (npm)
What this malware does
The package's index.js unconditionally loads bridge.js on require. bridge.js downloads a platform-specific native binary from obfuscated Cloudflare Workers hosts (oob-worker.cf101-adf.workers.dev, oob-worker.cf103-070.workers.dev, oob-worker.cf99-9b3.workers.dev), assembled at runtime by string concatenation (e.g. ["oob-work","er.cf99-9","b3.workers.","dev"].join("")) to evade plaintext scanning. The payload is written to a deceptive path (dotnet_diag<hex>.exe on Windows, /var/tmp/.cache<hex> on Unix), chmod 0755, and spawned detached via /bin/sh or cmd. When HTTPS fails, _bridge.js falls back to reconstructing the payload from base64 chunks retrieved via DNS TXT queries to *.dl.well1.site subdomains (tin/tina/ldr/win.dl.well1.site), also string-concat obfuscated, and executes it via the same chmod+spawn path — a covert channel designed to bypass HTTPS egress filtering. Cover-story comments ("Shuffle endpoints to distribute load", "Cache validation") and a persistence flag file named.analytics_state frame the dropper as telemetry. lib/telemetry.js additionally ships the same fetch/decode/chmod/spawn primitives (81 KB, framed as an Analytics SDK) as a dormant secondary loader, though not referenced from index.js in this version. The package is advertised as visual UI components, which has no purpose-aligned reason to fetch or execute native binaries.
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.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for platform-ui-island (version 20.5.9). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging platform-ui-island across your stack and pipelines.
If you installed it — respond
Remove platform-ui-island 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 platform-ui-island was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks platform-ui-island before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks platform-ui-island-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.