Re: [Full-disclosure] Getting Off the Patch

[Zach C <fxchip@xxxxxxxxx>]

On Jan 13, 2011, at 10:56 AM, Pete Herzog <lists@xxxxxxxxxx> wrote:

> Zach,
> 
> Please allow me to strip away any opinion for a moment and focus on the facts 
> which seem to be something we will agree on.
> 
> 1. A patch when applied changes the source code.
> 2. Patches are released AFTER a flaw is reported.
> 3. A patch will fix one or more reported flaws in the code.
> 4. The means to absolutely verify the true source of the patch requires that 
> your security has not already been compromised.
> 5. Evidence shows that patches, under the guise of security, have been used 
> in the past as a means for a company to change the function of their product, 
> remove content, or enforce licensing terms after it has been purchased and 
> installed on the computer.
> 6. Patching alone, without operational controls, has not shown to protect 
> systems or services consistently.
> 
> Therefore using the facts, we can logically conclude the following: For every 
> software, there are an unknown quantity of flaws. You protect the software 
> with multiple varied controls to protect against flaws both reported and not.

Seems logical; however...

> Therefore when you fix the flaw, you are only fixing a known and reported 
> flaw. This does not protect you against the unknown, unreported flaws still 
> existing and why you still need operational controls. So to say that you need 
> to patch to fix a flaw ignores all the flaws you don't know about.

While true, the patch is still most likely going to eliminate the flaw I *do* 
know about. I don't have either the connections or the time to find and know 
about some flaws that aren't covered by the patch, this is true; but I will 
know about the ones that are, and given my lack of connections, so do many 
other people, which increases the potential of exploitation (not the likelihood 
so much, but the potential). If I have the tools and the knowledge to fix a 
problem, I would figure that I would be remiss in not employing them merely 
because the other controls in place should keep my data safe. Especially if 
there is a direct interaction with what I'm patching and what I want to protect 
(website code & apache, can't expect it to work and not be able to read/run my 
code and such). 

The tl;dr summary of that, I guess, is "patching will at least keep the 
skiddies out."

> To fix each flaw in addition to adding controls adds new uncertainties both 
> to the software and the operational controls and requires further 
> verification testing to avoid surprise problems. A small change does not mean 
> it's a small test. To ignore the functional testing after patching is to 
> trust that the software maker knows your operations better than you, has your 
> best interest in mind above their own profits, and that is if you can even be 
> sure of where the patch came from.

Potentially, yes. However, it's not exactly like patches I can somewhat trust 
can come from anywhere else (unless I wrote it), and if I continue to use the 
software I probably trust its author. It also takes substantial effort to 
evaluate switching products entirely as opposed to patching what you currently 
have, but that's just stating the obvious. 

> Patch only because you can't control the interactions, can't stop the 
> interactions, don't do any quality control or functionality testing anyway, 
> or don't know if you've been already compromised anyway.
> 
> Sincerely,
> -pete.

All I'm really saying here is that controls external to what is weak are nice 
and definitely a recommendation, but ultimately can only mitigate what can be 
done. I'm saying it's generally worth it to patch for that extra assurance 
against well-known flaws -- but, granted, only especially so after a given 
period of time that sees many more and/or 'potentially fatal' flaws exposed to 
the public. 

Everything does make perfect sense though.

-Zach

> 
> On 1/11/2011 2:53 PM, Zach C wrote:
>> Hmm. So you propose other measures of security as a way of circumventing the 
>> requirement of patching vulnerable software. That's nice, but it occurs to 
>> me that the vulnerable software is still vulnerable, and sandboxing (as you 
>> mentioned in an example) isn't always possible or feasible -- maybe it 
>> requires a code change, who knows. I see you mention the time it takes to 
>> test patches and their effect on your workflow, but I would figure an equal 
>> or greater amount of time would then need to be spent on other solutions as 
>> well -- and even when those other solutions are implemented, the software 
>> that you're doing all this to is still vulnerable, and likely in a way that 
>> such measures can't really prevent all that well (code theft, etc).
>> 
>> Am I mistaken? I thought I got all that right. I haven't read the OSSTMM 3 
>> yet, granted (it's on my to-do list), but I would think that it's still 
>> worth doing all that -- just that disregarding patches entirely in favor of 
>> this isn't the solution either, which is probably not what you're saying. :)
>> 
>> On Jan 10, 2011, at 11:41 AM, Pete Herzog<lists@xxxxxxxxxx>  wrote:
>> 
>>> Hi,
>>> 
>>> Here's a new article on how and why you may want to stop patching your
>>> software and take a new approach to your security.
>>> 
>>> "So if patching is a tactic towards a particular security strategy,
>>> how can that be bad? I never said it was all bad. There are reasons
>>> where patching makes sense just like there are reasons to get a kick
>>> from a cup of coffee, get kicked by a shot of tequila, or spray stuff
>>> up your nose to breathe easier for 1.5 seconds. Yes, for the record, I
>>> am comparing patching to nasal spray."
>>> 
>>> Read it here:
>>> 
>>> https://www.infosecisland.com/blogview/10813-Getting-Off-the-Patch.html
>>> 
>>> Sincerely,
>>> -pete.
>>> 
>>> --
>>> Pete Herzog - Managing Director - pete@xxxxxxxxxx
>>> ISECOM - Institute for Security and Open Methodologies
>>> www.isecom.org - www.osstmm.org
>>> www.hackerhighschool.org - www.badpeopleproject.org
>>> 
>>> _______________________________________________
>>> Full-Disclosure - We believe in it.
>>> Charter: http://lists.grok.org.uk/full-disclosure-charter.html
>>> Hosted and sponsored by Secunia - http://secunia.com/
>> 
>> 
>> 
> 
> -- 
> Pete Herzog - Managing Director - pete@xxxxxxxxxx
> ISECOM - Institute for Security and Open Methodologies
> www.isecom.org - www.osstmm.org
> www.hackerhighschool.org - www.badpeopleproject.org

_______________________________________________
Full-Disclosure - We believe in it.
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