Team Cymru Mapped the Yurei Ransomware Toolkit Before It Could Strike

Team Cymru’s investigation mapped the Yurei ransomware operation—active since September 2025—by discovering open directories that revealed the attacker toolkit, links to Prince Ransomware and SatanLockv2, themed scripts and PDB strings, and evidence of a double-extortion model hosted on a Tor leak site; although no new victims were posted after the initial appearance, open directories as late as January 2026 suggest the operator may still be active.