FreeBSD Security Advisory FreeBSD-SA-14:08.tcp

[Xin Li]

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On 05/01/14 12:38, Ronald F. Guilmette wrote:
> I also have a question....
> 
> If one manages a system where (a) all local user accounts are
> completely and 100% trustworthy and where (b) one has in place ipfw
> rules which reject all incoming packet *fragments* on all
> outward-facing interfaces, then is this security problem (relating
> to the reassembly queue) an issue at all for said system?  Or is it
> rather a non-event in such contexts?

(a) doesn't matter, systems with only root user can be affected if they
provide TCP service.

(b) I'm not 100% sure on ipfw details (haven't used it for ~10 years
now) but IP fragmentation itself have nothing to do with this issue
since it's a different layer.  Assuming you can't do TCP reassemble
with ipfw, it's still a problem.

Cheers,
- -- 
Xin LI <delphij at delphij.net>    https://www.delphij.net/
FreeBSD - The Power to Serve!           Live free or die
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