Cl0p Affiliates Target Internet-Exposed PTC Windchill and FlexPLM with Unauthenticated RCE

Published on July 25, 2026

Threat actors linked to the Cl0p (aka Chubby Scorpius, FIN11, Graceful Spider, and Lace Tempest) ransomware campaign are exploiting flaws in internet-exposed PTC Windmill and FlexPLM deployments as part of a new data extortion campaign. "Attackers chain a pre-authentication information disclosure in the FlexPLM WSDL endpoint with a server-side flaw in the Windchill login servlet, enabling