Comment by mzajc
8 hours ago
I have yet to see a "NAT is not security" rebuttal that does not make either one or both of these points:
- NAT is not a security feature because it wasn't designed as one (this post), and/or
- NAT is not a security feature because it does not, without a firewall, protect against an attacker on the WAN subnet, or another difficult-to-exploit scenario.
And yet making LAN devices unroutable from the Internet does on its own makes exploitation much more difficult. It's admittedly not a perfect measure, but it's one that IPv6 deployments with routable addresses for LAN devices lack. I would wager this does make a difference in the proliferation of botnets, especially given the lackluster standards of consumer network equipment security.
You should read my other comments on this post. I've attempted, multiple times (but apparently without much success) to make the point that NAT is not a security feature because it does not, without a firewall, protect against an attacker.
You don't need a qualifier like "on the WAN subnet". It just doesn't do anything to protect you from inbound connections at all.
I think you're not technically wrong, but you're defining NAT differently than the majority of people you're arguing with (those who assume NAT also implies a firewall blocking inbound connections), and the remaining minority (the "on the WAN subnet" crowd) are dismissing outright the idea as a reasonable attack vector that an attacker close enough to be able to send packets destined for non-internet routable addresses to your router.
Is the latter something that was/is actively exploited?