The npm package @years18/n8n-nodes-utils-helper-d (version 1.0.0) masquerades as a community node for n8n but contains a malicious postinstall script (callback.js). This script disables TLS certificate validation to fetch and execute a remote archive containing a Python DDoS tool (mhddos). It also collects and exfiltrates system user and hostname information along with probing an internal TCP endpoint, sending this data encoded to an attacker-controlled URL. Additionally, it attempts to connect to a hardcoded internal IP address on port 8888, consistent with reconnaissance for lateral movement using a known offensive C2 framework (Sliver). The same malicious code is embedded in index.js to ensure execution upon module import.

Successful installation or import of this package results in remote code execution on the host system, unauthorized data exfiltration of system and network information, and internal network reconnaissance that could facilitate further compromise or lateral movement within the victim's environment.

No official patch or remediation is currently documented. Users should immediately avoid installing or using version 1.0.0 of @years18/n8n-nodes-utils-helper-d. Remove the package if already installed and investigate any potential compromise. Monitor for suspicious network activity related to the described attacker-controlled domains and internal network probes. Verify the integrity of dependencies before installation, especially community-contributed npm packages.