@cdnshell/loadernpm
Advisory published Updated
@cdnshell/loader is a confirmed malicious npm package (MAL-2026-14039) that executes malicious code on install (malicious versions 0.0.13, 0.0.14, 0.0.15…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @cdnshell/loader (npm)
What this malware does
Package presents itself as a CDN static-asset distribution library but ships 19 pre-compiled arm64 Mach-O binaries under 03_payloads/ (stager, kbridge, agent variants for iOS 13–19, including a64e/PAC variants). The binaries reference WebKit GPU-process IPC symbols (GPUConnectionToWebProcess_CreateRenderingBackend, RemoteRenderingBackend_GetPixelBufferForImageBufferWithNewMemory), private iOS entitlements (com.apple.private.webbookmarks.settings, DiagnosticReports.read-write), and mach_vm_/mach_port_ primitives consistent with a WebKit renderer-to-kernel exploit chain. The shipped JS entrypoint a12i5u6l.js is obfuscated with an obfuscator.io string-array/rotation scheme; after decoding, ModuleLoader.fetchModule fetches a manifest-selected module from a caller-configurable base URL and evaluates the response body via new Function(await response.text())() — a dynamic remote-code-execution sink. The surrounding orchestrator reads navigator.userAgent/platform and selects a payload variant from a hardcoded table that lines up with the shipped Mach-O stager/kbridge/agent set. There are no npm lifecycle hooks and no main, so the package does not execute on npm install or require(); the harm materializes when the loader is embedded in a webpage and served to iOS/macOS visitors, whose devices are then targeted by the WebKit exploit chain. The declared 'Static assets distribution' purpose, obfuscated loader, and prepositioned multi-version iOS Safari exploit payloads together are inconsistent with a legitimate static-asset library.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Search your lockfiles and build artifacts for @cdnshell/loader (7 malicious versions).
If you installed it — respond
Remove @cdnshell/loader 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 @cdnshell/loader 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 @cdnshell/loader-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.