The @flex-ng/filter-pipe package (version 1.1.0) was published to the npm registry by an attacker to conduct dependency confusion attacks. It uses a preinstall lifecycle hook to automatically run a script that installs the @sentry/node client and sends telemetry data including the public IP, hostname, OS username, and runtime metadata to an attacker-controlled Sentry DSN. This exfiltration is done by triggering a runtime exception that is captured and sent to the attacker's Sentry project. The package name mimics an internal organizational scope (@flex-ng) to increase the likelihood of installation in target environments with misconfigured package resolvers. The attack is reconnaissance-focused, allowing attribution of installs to specific organizations. The malicious payload is identical across packages published by this attacker, differing only in package name and Sentry project ID. The package is considered fully compromising to any system where it is installed.

Installation of this package results in the automatic exfiltration of sensitive host telemetry and environment metadata to an attacker-controlled endpoint without user knowledge or consent. This includes the public IP address, hostname, OS username, and runtime environment details. The presence of this package indicates a successful dependency confusion attack, potentially exposing internal organizational information and enabling further targeted attacks. According to the GHSA malware advisory, any system with this package installed should be considered fully compromised, and all secrets and keys on the system should be rotated immediately. Removal of the package alone may not remove all malicious artifacts or backdoors.

No official patch or fix is available for this malicious package. The recommended mitigation is to immediately remove the @flex-ng/filter-pipe package version 1.1.0 from all affected systems. Because the package executes code at install time that may fully compromise the system, all secrets and credentials stored on the affected systems should be rotated from a clean environment. Organizations should audit their package resolvers and dependency configurations to prevent dependency confusion attacks by ensuring private packages are resolved correctly and not overridden by public packages with similar names. Monitoring for suspicious packages published under organizational scopes and restricting package publishing permissions can help prevent similar attacks.