@sxm-web/client-sdk-corenpm
Advisory published Updated
@sxm-web/client-sdk-core is a confirmed malicious npm package (MAL-2026-18319) that opens a backdoor for remote access (malicious versions 0.0.1, 1.0.0, 1.0.1…). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in @sxm-web/client-sdk-core (npm)
What this malware does
@sxm-web/client-sdk-core is a dependency-confusion package: it is described as a "Compatibility shim", uses inflated version numbers, and its README calls it an "authorized dependency-confusion test". Each listed version (0.0.1, 1.0.0, 1.0.1, 2.0.0, 1.1.0, 3.0.0, 13.3.7) has a postinstall script that runs node beacon.cjs on npm install, and index.js calls the same code when the package is imported; it POSTs the hostname, install path and current working directory over plain HTTP to http://185.158.107.175:8787/_ah/dc, and index.js exports a Proxy that returns no-op functions so builds importing the real package keep running. The npm account wiseke published 14 such packages under the @greenlake, @sxm-web, @drone-js-ext and @ppa-web-components scopes between 2026-10-23 21:23 and 2026-10-25 14:28 UTC; index.js is byte-identical to that of ph-common (MAL-2026-1809), which sends to the same endpoint.
@sxm-web/[email protected] is a stub package whose only functional code is a beacon. The declared postinstall script runs node beacon.cjs, and the same beacon is also invoked at require time from index.js. The beacon collects installer-side identifiers (hostname, install path, current working directory, Node.js version, package name) and POSTs them in cleartext over plain HTTP to the hardcoded bare-IP endpoint http://185.158.107.175:8787/_ah/dc, which is unrelated to any legitimate registry or publisher infrastructure. The package's main returns a Proxy that produces no-op functions for every accessed property, so the package provides no advertised functionality — the install itself is the payload. The scoped name @sxm-web/client-sdk-core combined with a Compatibility shim description is consistent with a dependency-confusion probe aimed at an internal/private SDK namespace, where the beacon's purpose is to confirm successful resolution against private names and to disclose the resolving host's identity and filesystem layout to the operator at the bare IP.
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
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for @sxm-web/client-sdk-core (7 malicious versions).
If you installed it — respond
@sxm-web/client-sdk-core establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If @sxm-web/client-sdk-core 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
- InvisiRisk, Inc. · finder
Detect & block this
O3 blocks @sxm-web/client-sdk-core-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.