The malicious npm package @sapappgyver/appgyver-descriptors (version 9.9.11) includes an install lifecycle script that runs node index.js, which requires lib/core.js. This core module collects sensitive environment information such as the OS username, hostname, and current working directory basename. It encodes these details into a DNS subdomain and performs a DNS A record lookup to an attacker-controlled domain (oob.sl4x0.xyz), effectively leaking host and user identity. The code obfuscates module and property names using arrays of character code hex literals reconstructed at runtime. The package name is crafted to visually resemble SAP's legitimate @sap/appgyver-* scope, but the repository and author email are unrelated to SAP, indicating a malicious intent. According to the source ghsa-malware, any system with this package installed should be considered fully compromised.

Installation or use of this package results in leakage of sensitive host information to an attacker-controlled domain, potentially enabling further compromise. The package's presence indicates a full system compromise, with the attacker potentially having control over the affected machine. All secrets and keys stored on the compromised system should be considered exposed and require immediate rotation. Removing the package alone does not guarantee removal of all malicious artifacts or backdoors.

No official patch or fix is available. The package should be immediately removed from all systems. All secrets, credentials, and keys stored on affected machines must be rotated from a secure, uncompromised environment. Due to the high risk of full system compromise, affected systems should be thoroughly audited and potentially rebuilt to ensure removal of all malicious components.