Re: [saag] RADIUS is deprecating MD5

[Alan DeKok <[e-mail]>]

On Mar 31, 2024, at 9:59 AM, Peter Gutmann <[e-mail]> wrote:
> 
> Alan DeKok <[e-mail]> writes:
> 
>> Um... that is very much not what RADIUS is.
> 
> I'm not talking about RADIUS as RADIUS, I'm talking about RADIUS as a
> substrate for the next half-dozen layers up.

  The use-case you described was a very small, if not negligible one.  Both for RADIUS, and for the next few layers up.  Similarly, the comment about RADIUS being "not worth attacking" shows a misunderstanding of just how critical RADIUS is for the entire Internet.

> So it doesn't matter if, as used in that situation, RADIUS uses a Fletcher
> checksum for "security" or prepends the password to the first packet sent
> because it's acting only as a substrate for all the other layers, including
> the ones providing the security.  That's the case I mentioned, user =
> "anonymous", password = whatever (I've seen things like "anonymous",
> "password", "dummy", and others) because RADIUS isn't doing anything except
> meeting a requirement that it be present.

  I can only respond here by saying "no".

> Probably best for another thread, but if there aren't any major attacks
> against it occurring, as you mentioned previously, then it seems like
> attackers don't consider it worth attacking.

  Is it worth attacking a protocol which is in every single network switch, router, firewall, GGSN concentrator, etc. world-wide?  A protocol which, if successfully attacked, could give the attacker unfettered network access?

  I suspect that the answer to that is "yes".

  So why has no one done it?  Largely because no one cares.

  I'm not saying that I'm personally offended when people say bad things about RADIUS.  By all accounts it's a terrible protocol, and it's a bit of a miracle that it works.  I'm asking that criticisms of it be based on understanding what it is, and how it's used.

  Alan DeKok.