Hackers shoveled snow for company, were rewarded with network admin access

A professional red team bypassed physical security and network controls at a client site by posing as new IT staff and shoveling snow, planted a hidden Raspberry Pi on an unprotected conference-room Ethernet port, and over two weeks used password spraying and exploitation of AD Certificate Services (multiple ESC template/CA weaknesses) to escalate to domain administrator; the report highlights failures in badge/visitor checks, network access control, weak password policy, and lack of MFA.