How do threat actors laterally move and exploit internal system post-VPN Access?

Hello Friends,

We often read about incidents where threat actors exploit unpatched vulnerabilities in VPN servers and acquire VPN credentials through phishing emails with malicious attachments or social engineering.

However, I'm trying to deepen my understanding of what happens after they gain access to a victim's VPN.

Once inside the network via VPN, how do attackers typically move laterally to access other systems? How do attackers manage to access internal servers via SSH or RDP? I'm curious how they discover …

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