I came across a Reddit thread about someone using a neighbour’s WiFi, and the (unknown) neighbour later changed the ssid to the user’s gaming handle.

Lots of comments saying that public WiFi can be a trap, and a malicious actor can see all your packets, sniff your passwords, spoof login pages… And not one refuting it with SSL.

Am I missing something?! Is a WiFi/LAN actually that dangerous? I thought pretty much every site and service uses SSL these days, and signed certificates so (unless you have a particular Lenovo or Dell model) DNS spoofing won’t work.

And aren’t most ports on your own computer closed by default now? Unless you’ve opened ssh or a samba share with a poor password or something?

I realise packets can still be sniffed, website use can be tracked (but not the data, not things like passwords). With more work, that could be correlated to, for instance, what time a user logs on to a discord server.

Have I missed something big? Is someone else’s WiFi or LAN actually dangerous?

  • milicent_bystandr@lemm.eeOP
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    5 days ago

    Most cryptographic protocols include some form of endpoint authentication specifically to prevent MITM attacks. For example, TLS can authenticate one or both parties using a mutually trusted certificate authority.

    For most purposes, doesn’t HTTPS thwart MITM attacks? It’s designed to be resilient against MITM for the whole chain through your ISP and other gateways to the destination, no?

    • taladar@sh.itjust.works
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      5 days ago

      Only if you start with HTTPS but browsers have favored HTTP for backwards compatibility as the default protocol when something is entered in the address bar until very recently (less than a year for any browser to do that by default via HTTPS). Usually users don’t notice because websites redirect to HTTPS but technically a MITM attacker could just redirect you somewhere else.

      • u/lukmly013 💾 (lemmy.sdf.org)@lemmy.sdf.org
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        5 days ago

        But even then, theoretically, even if not default, could you not just block the first request to HTTPS site causing fallback to HTTP and then redirect elsewhere for the purpose of nice lock icon?

        • taladar@sh.itjust.works
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          5 days ago

          If you have a HTTP fallback on HTTPS failure that might work, but only if the site doesn’t use HSTS and this is the first request on that client. I skipped over HSTS preloading in my earlier explanation which also addresses this issue for sites on the browsers list at least.