📅 Original date posted:2016-06-28
📝 Original message:> On Jun 28, 2016, at 10:14 PM, Peter Todd <pete at petertodd.org> wrote:
>
>> On Tue, Jun 28, 2016 at 08:35:26PM +0200, Eric Voskuil wrote:
>> Hi Peter,
>>
>> What in this BIP makes a MITM attack easier (or easy) to detect, or increases the probability of one being detected?
>
> BIP151 gives users the tools to detect a MITM attack.
>
> It's kinda like PGP in that way: lots of PGP users don't properly check keys,
PGP requires a secure side channel for transmission of public keys. How does one "check" a key of an anonymous peer? I know you well enough to know you wouldn't trust a PGP key received over an insecure channel.
All you can prove is that you are talking to a peer and that communications in the session remain with that peer. The peer can be the attacker. As Jonas has acknowledged, authentication is required to actually guard against MITM attacks.
> so an attacker won't have a hard time MITM attacking those users. But some
> users do check keys, a labor intensive manual process, but not a process that
> requires any real cryptographic sophistication, let alone writing any code.
> It's very difficult for widescale attackers to distinguish the users who do
> check keys from the ones that don't, so if you MITM attack _any_ user you run
> the risk of running into one of the few that does check, and those users can
> alert everyone else.
>
> The key thing, is we need to get everyones communications encrypted first: if
> we don't the MITM attacker can intercept 99% of the communications with 0% risk
> of detection, because the non-sophisticated users are trivially distinguishable from the sophisticated users: just find the users with unencrypted
> communications!
>
> --
> https://petertodd.org 'peter'[:-1]@petertodd.org
Eric Voskuil [ARCHIVE] /
npub1sg…ppx3c
2023-06-07 17:51:37
in reply to nevent1q…kpm0
Author Public Key
npub1sgs97fe0n9wehe6zw7drcxdz4cy9yt9pfqjv8gasz5jlk4zezc0quppx3cPublished at
2023-06-07 17:51:37Event JSON
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"content": "📅 Original date posted:2016-06-28\n📝 Original message:\u003e On Jun 28, 2016, at 10:14 PM, Peter Todd \u003cpete at petertodd.org\u003e wrote:\n\u003e \n\u003e\u003e On Tue, Jun 28, 2016 at 08:35:26PM +0200, Eric Voskuil wrote:\n\u003e\u003e Hi Peter,\n\u003e\u003e \n\u003e\u003e What in this BIP makes a MITM attack easier (or easy) to detect, or increases the probability of one being detected?\n\u003e \n\u003e BIP151 gives users the tools to detect a MITM attack.\n\u003e \n\u003e It's kinda like PGP in that way: lots of PGP users don't properly check keys,\n\nPGP requires a secure side channel for transmission of public keys. How does one \"check\" a key of an anonymous peer? I know you well enough to know you wouldn't trust a PGP key received over an insecure channel.\n\nAll you can prove is that you are talking to a peer and that communications in the session remain with that peer. The peer can be the attacker. As Jonas has acknowledged, authentication is required to actually guard against MITM attacks.\n\n\u003e so an attacker won't have a hard time MITM attacking those users. But some\n\u003e users do check keys, a labor intensive manual process, but not a process that\n\u003e requires any real cryptographic sophistication, let alone writing any code.\n\u003e It's very difficult for widescale attackers to distinguish the users who do\n\u003e check keys from the ones that don't, so if you MITM attack _any_ user you run\n\u003e the risk of running into one of the few that does check, and those users can\n\u003e alert everyone else.\n\u003e \n\u003e The key thing, is we need to get everyones communications encrypted first: if\n\u003e we don't the MITM attacker can intercept 99% of the communications with 0% risk\n\u003e of detection, because the non-sophisticated users are trivially distinguishable from the sophisticated users: just find the users with unencrypted\n\u003e communications!\n\u003e \n\u003e -- \n\u003e https://petertodd.org 'peter'[:-1]@petertodd.org",
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