Microsoft Security Blog · May 22, 2026

From edge appliance to enterprise compromise: Multi-stage Linux intrusion via F5 and Confluence

Why it matters

A multi-stage attack on Linux devices began with an exposed F5 BIG-IP edge appliance and pivoted to an internal Confluence server for credential theft and identity compromise. Learn how the threat actor attempted Kerberos relay and lateral movement, and how Microsoft Defender detected, blocked, and unraveled the attack

My takeaway: A multi-stage attack on Linux devices began with an exposed F5 BIG-IP edge appliance and pivoted to an internal Confluence server for credential theft and identity compromise. Learn how the threat actor attempted Kerberos relay and lateral movement, and how Microsoft Defender detected, blocked, and unraveled the attack