Messages in this thread | | | Date | Fri, 1 Mar 2013 00:45:23 +0100 (CET) | From | Jiri Kosina <> | Subject | Re: [GIT PULL] Load keys from signed PE binaries |
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On Thu, 28 Feb 2013, Matthew Garrett wrote:
> > But the real harm is being done by the i_own_your_ring0.ko module, which > > can be modprobed on all the systems where the signed "hello world" binary > > has been keyctl-ed before it was blacklisted. > > Sure, if you've been infected before the revocation, you'll still be > infected. There's not really any good way around that.
Which is a very substantial difference to normal X509 chain of trust, isn't it?
This security model seems to be quite seriously flawed to me (in a sense that it has nothing to do with chain of trust as mandated by X509 even though it tries to pretend the opposite)
And frankly, Linus' proposal at [1] doesn't really make it any better in principle, it just keeps the whole thing out of kernel.
[1] https://lkml.org/lkml/2013/2/21/228
> > In other words -- you blacklist the population of the key on systems by > > blakclisting the key-carrying binary, but the key remains trusted on > > whatever system the binary has been processed by keyctl before. Right? > > You have to re-load it on every boot, it's not a permanent thing.
That unfortunately seems to be very weak security measure as well.
Thanks,
-- Jiri Kosina SUSE Labs
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