The active-support ruby gem gem is malware and duplicates the official activesupport (no hyphen) gem, but adds a compiled extension. The extension attempts to resolve a base64 encoded domain (29faea63.planfhntage.de), downloads a payload, and executes.
This trojan horse gem could allow a remote attacker to execute arbitrary code on the system, caused by containing a malicious backdoor. An attacker could exploit this vulnerability to execute arbitrary code on the system. No version of this gem should be considered safe.
Checked 2026-10-04 at 01:11 UTC. The most recent advisory here was published 2018-08-13. Updated continuously from NVD, GHSA, OSV and CNA feeds.