How Azure JIT works on VM

How Azure's JIT VM Access Works

Ever worry about those open RDP/SSH ports on your Azure VMs? You should! They're a prime target for attackers. But with Just-in-Time (JIT) VM access, part of Microsoft Defender for Cloud, you can keep them locked down tight.

How JIT Protects Your VMs:

1. Ports Closed by Default: Imagine your VM's management ports (like RDP 3389 or SSH 22) are always shut. JIT ensures this by configuring your Network Security Groups (NSGs) to deny all inbound traffic to these ports. No open doors for attackers!

2. Access On-Demand: When an admin actually needs to connect, they simply request access through the Azure portal. They specify:

   • Which VM

   • Which port

   • Their specific IP address

   • How long they need access (e.g., 1 hour).

3. Temporary Opening, Auto-Closing: Defender for Cloud verifies the request, then dynamically creates a temporary "allow" rule just for that user, from their IP, for that specific time. Once the time is up, the rule is automatically removed, and the port is instantly locked down again.

4. Full Audit Trail: Every access request and connection is logged, giving you complete visibility for security and compliance.

Why Use JIT?

• Massively Reduces Attack Surface: Keeps ports closed when not needed.

• Time-Bound Access: No more forgotten open ports.

• Granular Control: Precise access for specific users from specific IPs.

• Boosts Security Posture: Enforces a "least privilege" approach for VM access.

JIT VM access is a simple, effective way to elevate your Azure VM security without hindering legitimate access. Lock it down, open it just-in-time!