[Cryptography] New SSL/TLS certs to each live no longer than 47 days by 2029

[Ron Garret]

> On Apr 21, 2025, at 2:38 PM, iang via cryptography <cryptography at metzdowd.com> wrote:
> 
> On 20/04/2025 18:13, Kent Borg wrote:
>> I thought I saw someone here shrugging off the risk of MitM attacks. Be careful.
> 
> 'twas me, heretic in chief.
> 
> The issue here is that SSL was brought in (from v1 to v2) because of the claim that MITMs would eat our lunch. That was an unevidenced claim, and since then, there has been no evidence that the MITM attack justifies that level of defence.

But that's because the defense is in place.  It's plausible that the reason we're not seeing MITM attacks is because the defense is effective.

> I'm not saying it does or doesn't - I'm saying we don't know.

That's kind of like saying that until you actually try jumping off the Eiffel Tower you can't know for certain whether or not you will plummet to your death, and so until someone actually does this experiment the guard rails are useless.

>> An awful lot of users connect via wifi, and, as flawed as the
>> certificate system is, it makes it hard for random evil hotspots to
>> pretend to be your bank or your e-mail. If we were back at plain http
>> these attacks would be a big problem. The system does work…to the extent
>> it works.
> 
> Which is (1) the evidence-free assertion. Are we protecting ourselves against a rainbow unicorn attack? It matters less if the defence works than if rainbow unicorns actually do attack.

But you don't have to posit rainbow unicorns.  All you need is a script kiddie with a Raspberry Pi, and those are not mythical creatures.  It seems pretty implausible that no one would attempt MITM attacks if it were possible to conduct them with low effort and low risk.

> One example: SSH was born because people discovered that internal attackers were eavesdropping root passwords on ethernet LANs, and hacking into machines. So RSH was updated to add keys & crypto. Problem solved correctly, because attacks were happening, and the solution stopped those attacks.

The stakes are much higher now.  Suggesting that MITM mitigation is useless until people actually start geetting their bank account compromised on the regular seems pretty irresponsible to me.

I also at this point feel the need to point out that your hypothesis is *quite literally* a conspiracy theory.

rg