OpenSSF/OSV advisory MAL-2026-5491 confirms this npm version as malicious. The package ships scripts/script.js containing heavy obfuscation patterns (string-array shift rotation, hex-encoded numeric literals, while(!![]) control-flow flattening). Obfuscated code in install-time scripts is uncharacteristic of legitimate SDK distributions, which typically ship readable JavaScript or, at most, minified bundles...
Source
OpenSSF Malicious Packages via OSV
Summary
Malicious code in xnder-sdk (npm)
Details
The package ships scripts/script.js containing heavy obfuscation patterns (string-array shift rotation, hex-encoded numeric literals, while(!![]) control-flow flattening). Obfuscated code in install-time scripts is uncharacteristic of legitimate SDK distributions, which typically ship readable JavaScript or, at most, minified bundles. The obfuscation prevents straightforward verification of what the script does on installer machines. Without de-obfuscating the script and confirming whether it performs network I/O, credential reads, or code execution at install or require time, the specific installer-side behavior cannot be characterized.
## Source: ghsa-malware (4dfcb759dd36ce1ba707484f0a2735cafb5b97844e860ffc8646f93be9731b90) 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.
Decision reason
OpenSSF Malicious Packages via OSV confirms xnder-sdk@11.0.3 as malicious (MAL-2026-5491): Malicious code in xnder-sdk (npm)