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Firewall Types – What "Evasion" Means to Blue
Firewall Types – What "Evasion" Means to Blue The main firewall types: packet filter, stateful, and application/next-gen (NGFW). Not a magic packet. Usually a policy hole : an open outbound rule, or an allowed app being abused. Review allow-lists. Log denied traffic. Default-deny inbound, and also t
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What this card says
What it is
The main firewall types: packet filter, stateful, and application/next-gen (NGFW).
What “evasion” really means
Not a magic packet. Usually a policy hole: an open outbound rule, or an allowed app being abused.
Defence
Review allow-lists. Log denied traffic.
Default-deny inbound, and also think about outbound rules, since malware connects out.
| Type | Idea |
|---|---|
| Packet filter | Per-packet IP/port (classic iptables filter, simple SG) |
| Stateful | Tracks TCP/UDP "this is a reply" (firewalld/nftables… |
| WAF | HTTP/S app rules (OWASP CRS / ModSecurity class) |
| NGFW | App-ID, user-ID, SSL decrypt (policy), IPS blade |
Learn more in the lesson: 42.5 Firewall Types – What "Evasion" Means to Blue