Debian/Ubuntu: Why was the service renamed from bind9 to named?

Michael De Roover isc at nixmagic.com
Thu Jul 23 13:49:37 UTC 2020


The idea is pretty interesting, seems like they provide a repository 
with packages compiled with their own compiler that changes various 
memory-related elements. It is true that memory is usually the culprit 
behind security flaws.

According to their page at 
https://polyverse.com/products/polymorphing-linux-security/ :

"Polymorphing takes source code and runs it through a polymorphic 
compiler, changing register usage, function locations, import tables and 
other targets. This produces individually unique binaries that are 
semantically equivalent to the source. Polymorphing applies the compiler 
to the totality of the Linux stack."

For this to work at all though, they'd have to provide all packages 
simply as source code (why not use the distribution's own source 
repositories?) and compile it on the target. But even then I think it's 
more of a security by obscurity thing. Sure it makes it more difficult 
to exploit a memory flaw by means of automated exploits and other such 
scripts. But nothing stops you from taking the unmodified source code, 
the binary and a disassembler to find out how exactly the resulting 
binary has been changed / polymorphed. I'm not very familiar with 
reverse engineering and disassemblers but I don't think there's much 
more to it than that, at least to thwart this defense. All of it is 
possible if an attacker can read, retrieve and execute a binary on the 
affected server. The flaws are still there, only their memory locations 
have changed. It would probably defend against script kiddies, but I 
doubt it would keep out a determined attacker.

Personally I prefer Google's approach to this for Chromium. They 
documented it at 
https://chromium.googlesource.com/chromium/src/+/master/docs/security/rule-of-2.md 
. Implementing programs in memory safe languages where possible is 
something I believe to be a more solid long-term solution. Additionally 
Google's Project Zero team is behind a lot of the security research and 
disclosures. They audit the actual code instead, which I believe to be 
far more suitable.

While the idea is valid to some extent (and could be worth it in highly 
confidential environments), I wouldn't consider it worth compiling 
everything from source for, with a nonstandard compiler no less. If 
servers would just be updated more often and (security) bug fixes 
actually make their way through to the distribution releases reliably, 
we'd already go a long way I think. Of course there are also 
configuration mistakes that could compromise a network component. From 
what I've seen so far, this seems to be more often the case with those 
leaked databases and whatnot.

On 7/23/20 2:39 PM, Fred Morris wrote:
> Perhaps slightly OT, but here's a company which has a whole business 
> model based on one nonobvious (?) reason to compile from source: 
> https://polyverse.com/
>
> -- 
>
> Fred Morris
-- 
Met vriendelijke groet / Best regards,
Michael De Roover


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